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  • Energy, Environment Protection, Nuclear Power Engineering  (62,485)
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  • 1
    Publication Date: 2015-08-11
    Description: In order to achieve process intensification for adsorption chillers and heat pumps, a new composite material was developed based on sintered aluminum fibers from a melt-extraction process and a dense layer of silico-aluminophosphate (SAPO-34) on the fiber surfaces. The SAPO-34 layer was obtained through a partial support transformation (PST) process. Preparation of a composite sample is described and its characteristic pore size distribution and heat conductivity are presented. Water adsorption data obtained under conditions of a large pressure jump are given. In the next step, preparation of the composite was scaled up to larger samples which were fixed on a small adsorption heat exchanger. Adsorption measurements on this heat exchanger element that confirm the achieved process intensification are presented. The specific cooling power for the adsorption step per volume of composite is found to exceed 500 kW/m3 under specified conditions.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 2
    Publication Date: 2015-08-08
    Description: The relationship between soil fauna and different fertilizer management practices is of growing concern. The aim of this research was to investigate the response of soil fauna to fertilization regimes, to explore the relationships among the community of soil animals, soil moisture and crop yields. The application of organic fertilizers (i.e., sheep manure or crop residues) increased crop yields and promoted the number of individuals and species of soil fauna owing to the exogenous organic matter that fertilizers provided for the survival and development of soil fauna. Furthermore, the treatments that applied sheep manure (i.e., sheep manure only or nitrogen, phosphorus, potassium and sheep manure plus) were significantly beneficial for increasing crop yields and diversity of soil fauna compared to treatments with crop residues returned (i.e., crop residues returned only or nitrogen, phosphorus, potassium and crop residues returned to the field) (p 〈 0.05) due to the response of soil fauna to diverse exogenous nutrients and the effect of soil fertility. Therefore, the finding that soil fauna abundance is significantly positively correlated with soil moisture and crop yield may mean the effects of fertilizer applications on soil animals were partly masked by the soil moisture and crop yield.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 3
    Publication Date: 2015-08-12
    Description: This paper provides an overview of the main manufacturing technologies of displays, focusing on those with low and ultra-low levels of power consumption, which make them suitable for current societal needs. Considering the typified value obtained from the manufacturer’s specifications, four technologies—Liquid Crystal Displays, electronic paper, Organic Light-Emitting Display and Electroluminescent Displays—were selected in a first iteration. For each of them, several features, including size and brightness, were assessed in order to ascertain possible proportional relationships with the rate of consumption. To normalize the comparison between different display types, relative units such as the surface power density and the display frontal intensity efficiency were proposed. Organic light-emitting display had the best results in terms of power density for small display sizes. For larger sizes, it performs less satisfactorily than Liquid Crystal Displays in terms of energy efficiency.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 4
    Publication Date: 2015-08-12
    Description: This study forecasts the liquidity gap in China’s pension scheme for urban workers in the context of an ageing population and the possible effects of recent governmental policies by constructing a basic pension model, including “old people”, “middle people” and “new people” and a simulation method. We find, firstly, that China’s liquidity gap of pension will reach its peak of approximately 13.11 trillion yuan in 2038. Subsequently, this gap will gradually decrease with growth in the mortality rate. Secondly, reasonable intervals for the replacement and contribution rates should be set at [0.417, 0.604] and [0.189, 0.262], respectively, to sustain China’s pension system. Thirdly, compared to increasing fiscal subsidies, an income doubling plan, raising the contribution rate, lowering the replacement rate and delaying the retirement age can significantly reduce the liquidity gap, although the policy costs are relatively high. A policy permitting families to have two children will increase the rate of reduction of the liquidity gap, but it cannot effectively narrow the gap at the peak moment.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 5
    Publication Date: 2015-08-13
    Description: Accurate state of charge (SoC) estimation of batteries plays an important role in promoting the commercialization of electric vehicles. The main work to be done in accurately determining battery SoC can be summarized in three parts. (1) In view of the model-based SoC estimation flow diagram, the n-order resistance-capacitance (RC) battery model is proposed and expected to accurately simulate the battery’s major time-variable, nonlinear characteristics. Then, the mathematical equations for model parameter identification and SoC estimation of this model are constructed. (2) The Akaike information criterion is used to determine an optimal tradeoff between battery model complexity and prediction precision for the n-order RC battery model. Results from a comparative analysis show that the first-order RC battery model is thought to be the best based on the Akaike information criterion (AIC) values. (3) The real-time joint estimator for the model parameter and SoC is constructed, and the application based on two battery types indicates that the proposed SoC estimator is a closed-loop identification system where the model parameter identification and SoC estimation are corrected mutually, adaptively and simultaneously according to the observer values. The maximum SoC estimation error is less than 1% for both battery types, even against the inaccurate initial SoC.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 6
    Publication Date: 2015-08-13
    Description: This is the second part of a study conducted to model the aerothermodynamic impact of suction parameters and gas properties on a multi-stage centrifugal compressor’s performance. A new iterative method has been developed in the first part to derive the equivalent performance at various operating conditions. This approach has been validated to predict the compressor map at different suction pressures and temperatures using the design characteristics as reference values. A further case is included in this paper in order to emphasize the validity of the developed approach to obtain the performance characteristics at various gas compositions. The provided example shows that the performance parameters at different gas mixtures can be predicted to within ±1.34%. Furthermore, the conducted optimization in this paper reveals that the proposed method can be applied for the compressor design evaluation corresponding to the expected variation in suction conditions. Moreover, the examined case study demonstrates the effect of gas properties’ variation on the operating point and aerodynamic stability of the entire compression system. In order to achieve that, a simple approach has been established to assess the contribution of gas properties’ variation to the inefficient and unstable compressor performance based on the available operational data.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 7
    Publication Date: 2015-08-13
    Description: The in-wheel electric vehicle is expected to be a popular next-generation vehicle because an in-wheel system can simplify the powertrain and improve driving performance. In addition, it also has an advantage in that it maximizes driving efficiency through independent torque control considering the motor efficiency. However, there is an instability problem if only the driving torque is controlled in consideration of only the motor efficiency. In this paper, integrated torque distribution strategies are proposed to overcome these problems. The control algorithm consists of various strategies for optimizing driving efficiency, satisfying driver demands, and considering tire slip and vehicle cornering. Fuzzy logic is used to determine the appropriate timing of intervention for each distribution strategy. A performance simulator for in-wheel electric vehicles was developed by using MATLAB/Simulink and CarSim to validate the control strategies. From simulation results under complex driving conditions, the proposed algorithm was verified to improve both the driving stability and fuel economy of the in-wheel vehicle.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 8
    Publication Date: 2015-08-13
    Description: The knowledge of unsteady forces is necessary when designing vertical axis wind turbines (VAWTs). Measurement data for turbines operating at an open site are still very limited. The data obtained from wind tunnels or towing tanks can be used, but have limited applicability when designing large-scale VAWTs. This study presents experimental data on the normal forces of a 12-kW straight-bladed VAWT operated at an open site north of Uppsala, Sweden. The normal forces are measured with four single-axis load cells. The data are obtained for a wide range of tip speed ratios: from 1.7 to 4.6. The behavior of the normal forces is analyzed. The presented data can be used in validations of aerodynamic models and the mechanical design for VAWTs.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 9
    Publication Date: 2015-08-13
    Description: This paper introduces a new iterative method to predict the equivalent centrifugal compressor performance at various operating conditions. The presented theoretical analysis and empirical correlations provide a novel approach to derive the entire compressor map corresponding to various suction conditions without a prior knowledge of the detailed geometry. The efficiency model was derived to reflect the impact of physical gas properties, Mach number, and flow and work coefficients. One of the main features of the developed technique is the fact that it considers the variation in the gas properties and stage efficiency which makes it appropriate with hydrocarbons. This method has been tested to predict the performance of two multistage centrifugal compressors and the estimated characteristics are compared with the measured data. The carried comparison revealed a good matching with the actual values, including the stable operation region limits. Furthermore, an optimization study was conducted to investigate the influences of suction conditions on the stage efficiency and surge margin. Moreover, a new sort of presentation has been generated to obtain the equivalent performance characteristics for a constant discharge pressure operation at variable suction pressure and temperature working conditions. A further validation is included in part two of this study in order to evaluate the prediction capability of the derived model at various gas compositions.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 10
    Publication Date: 2015-08-13
    Description: This paper presents an investigation of sewage sludge gasification in a fixed bed gasifier. Experiments were conducted on a laboratory scale fixed bed gasifier. In the experiments, two types of dried sewage sludge were tested and their properties were analysed. Parameters such as air ratio λ = 0.12 to 0.27, gasification agent temperature t = 50 to 250 °C and gasification agent composition ( = 0.21 and  > 0.21) were found to influence on temperature distribution, syngas Lower Heating Value (LHV) and syngas composition. The results indicate that the syngas LHV was found to decrease with increased air ratio for all analyzed cases: cold and preheated air and cold enriched air. The increase in the percentage of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Increasing oxygen concentration increased the temperature, which tended to favor the formation of smaller molecules in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional gasification, gasification process with gasification agent preheating causes that the flux of heat necessary to support endothermic gasification reactions is producing more effective. Air preheating causes increases hydrogen and carbon monoxide production.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 11
    Publication Date: 2015-08-15
    Description: Atmospheric concentrations of carbon dioxide (CO2), a major cause of global warming, have been rising due to industrial development. Carbon capture and storage (CCS), which is regarded as the most effective way to reduce such atmospheric CO2 concentrations, has several environmental and technical disadvantages. Carbon capture and utilization (CCU), which has been introduced to cover such disadvantages, makes it possible to capture CO2, recycling byproducts as resources. However, CCU also requires large amounts of energy in order to induce reactions. Among existing CCU technologies, the process for converting CO2 into CaCO3 requires high temperature and high pressure as reaction conditions. This study proposes a method to fixate CaCO3 stably by using relatively less energy than existing methods. After forming NaOH absorbent solution through electrolysis of NaCl in seawater, CaCO3 was precipitated at room temperature and pressure. Following the experiment, the resulting product CaCO3 was analyzed with Fourier transform infrared spectroscopy (FT-IR); field emission scanning electron microscopy (FE-SEM) image and X-ray diffraction (XRD) patterns were also analyzed. The results showed that the CaCO3 crystal product was high-purity calcite. The study shows a successful method for fixating CO2 by reducing carbon dioxide released into the atmosphere while forming high-purity CaCO3.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 12
    Publication Date: 2015-08-04
    Description: The effect of fuel composition on gasification process performance was investigated by performing mass and energy balances on a pre-pilot scale bubbling fluidized bed reactor fed with mixtures of plastic waste, wood, and coal. The fuels containing plastic waste produced less H2, CO, and CO2 and more light hydrocarbons than the fuels including biomass. The lower heating value (LHV) progressively increased from 5.1 to 7.9 MJ/Nm3 when the plastic waste fraction was moved from 0% to 100%. Higher carbonaceous fines production was associated with the fuel containing a large fraction of coal (60%), producing 87.5 g/kgFuel compared to only 1.0 g/kgFuel obtained during the gasification test with just plastic waste. Conversely, plastic waste gasification produced the highest tar yield, 161.9 g/kgFuel, while woody biomass generated only 13.4 g/kgFuel. Wood gasification showed a carbon conversion efficiency (CCE) of 0.93, while the tests with two fuels containing coal showed lowest CCE values (0.78 and 0.70, respectively). Plastic waste and wood gasification presented similar cold gas efficiency (CGE) values (0.75 and 0.76, respectively), while that obtained during the co-gasification tests varied from 0.53 to 0.73.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 13
    Publication Date: 2015-08-06
    Description: The current accelerated growth in demand for energy globally is confronted by water-resource limitations and hydrologic variability linked to climate change. The global spatial and temporal trends in water requirements for energy development and policy alternatives to address these constraints are poorly understood. This article analyzes national-level energy demand trends from U.S. Energy Information Administration data in relation to newly available assessments of water consumption and life-cycle impacts of thermoelectric generation and biofuel production, and freshwater availability and sectoral allocations from the U.N. Food and Agriculture Organization and the World Bank. Emerging, energy-related water scarcity flashpoints include the world’s largest, most diversified economies (Brazil, India, China, and USA among others), while physical water scarcity continues to pose limits to energy development in the Middle East and small-island states. Findings include the following: (a) technological obstacles to alleviate water scarcity driven by energy demand are surmountable; (b) resource conservation is inevitable, driven by financial limitations and efficiency gains; and (c) institutional arrangements play a pivotal role in the virtuous water-energy-climate cycle. We conclude by making reference to coupled energy-water policy alternatives including water-conserving energy portfolios, intersectoral water transfers, virtual water for energy, hydropower tradeoffs, and use of impaired waters for energy development.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 14
    Publication Date: 2015-08-06
    Description: In the last decades the increasing energy requirements along with the need to face the consequences of climate change have driven the search for renewable energy sources, in order to replace as much as possible the use of fossil fuels. In this context biomass has generated great interest as it can be converted into energy via several routes, including fermentation and anaerobic digestion. The former is the most common option to produce ethanol, which has been recognized as one of the leading candidates to substitute a large fraction of the liquid fuels produced from oil. As the economic competitiveness of bioethanol fermentation processes has to be enhanced in order to promote its wider implementation, the most recent trends are directed towards the use of fermentation by-products within anaerobic digestion. The integration of both fermentation and anaerobic digestion, in a biorefinery concept, would allow the production of ethanol along with that of biogas, which can be used to produce heat and electricity, thus improving the overall energy balance. This work aims at reviewing the main studies on the combination of both bioethanol and biogas production processes, in order to highlight the strength and weakness of the integrated treatment for industrial application.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 15
    Publication Date: 2015-08-06
    Description: During the last few years, the issues of energy efficiency and energy saving have dominated the buildings research field. New constructions are based on efficient design and, because of this, the real challenge is to retrofit existing buildings. Italian standards impose thermal transmittance limits for opaque and transparent surfaces, according to the climatic area. In order to understand buildings’ energy behavior, an accurate analysis, carried out by employing advanced calculation codes and instrumental diagnosis—provided by the use of heat flow meter, surface temperature probes and thermal imaging camera—is needed. In this paper, a structure built in the 50 s has been analyzed, by means of a measurement campaign, to investigate the building’s characteristics and its vulnerability. Finally, some retrofit hypotheses have been evaluated by means of a well-known dynamic code. All investments have to be analyzed under a financial point of view, considering materials and installation costs. For this reason, the payback time has been calculated in order to understand how quickly the energy upgrading can be repaid.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 16
    Publication Date: 2015-08-08
    Description: We propose an optimal electric energy management of a cooperative multi-microgrid community with sequentially coordinated operations. The sequentially coordinated operations are suggested to distribute computational burden and yet to make the optimal 24 energy management of multi-microgrids possible. The sequential operations are mathematically modeled to find the optimal operation conditions and illustrated with physical interpretation of how to achieve optimal energy management in the cooperative multi-microgrid community. This global electric energy optimization of the cooperative community is realized by the ancillary internal trading between the microgrids in the cooperative community which reduces the extra cost from unnecessary external trading by adjusting the electric energy production amounts of combined heat and power (CHP) generators and amounts of both internal and external electric energy trading of the cooperative community. A simulation study is also conducted to validate the proposed mathematical energy management models.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 17
    Publication Date: 2015-08-07
    Description: Congestion pricing strategy has been recognized as an effective countermeasure in the practical field of urban traffic congestion mitigation. In this paper, a bi-level programming model considering carbon dioxide emission is proposed to mitigate traffic congestion and reduce carbon dioxide emissions. The objective function of the upper level model is to minimize the sum of travel costs and the carbon dioxide emissions costs. The lower level is a multi-modal transportation network equilibrium model. To solve the model, the method of successive averages (MSA) and the shuffled frog leaping algorithm (SFLA) are introduced. The proposed method and algorithm are tested through the numerical example. The results show that the proposed congestion pricing strategy can mitigate traffic congestion and reduce carbon emissions effectively.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 18
    Publication Date: 2015-08-18
    Description: We investigated the synergetic effect between light-emitting diode (LED) lighting efficiency and building energy savings in heating and cooling using an alternative thermal operating system (ATOS) of indoor LED lighting integrated with the ventilation system of a building as an active cooling device. The heat generated from LED lighting and the indoor lighting illuminance were experimentally determined. The indoor heat gains in cooling and heating periods were determined using measurement data; the annual energy savings of an office building in heating and cooling were calculated through simulation. The LED lighting illuminance increased by approximately 40% and the lighting contribution for indoor heat gain was 7.8% in summer, while 69.8% in winter with the ATOS. Consequently, the annual total energy use of the office building could be reduced by 5.9%; the energy use in cooling and heating was reduced by 18.4% and 3.3%, respectively.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 19
    Publication Date: 2015-08-19
    Description: The internet and associated Information and Communications Technologies (ICT) are diffusing at an astounding pace. As data centers (DCs) proliferate to accommodate this rising demand, their environmental impacts grow too. While the energy efficiency of DCs has been researched extensively, their water footprint (WF) has so far received little to no attention. This article conducts a preliminary WF accounting for cooling and energy consumption in DCs. The WF of DCs is estimated to be between 1047 and 151,061 m3/TJ. Outbound DC data traffic generates a WF of 1–205 liters per gigabyte (roughly equal to the WF of 1 kg of tomatos at the higher end). It is found that, typically, energy consumption constitues by far the greatest share of DC WF, but the level of uncertainty associated with the WF of different energy sources used by DCs makes a comprehensive assessment of DCs’ water use efficiency very challenging. Much better understanding of DC WF is urgently needed if a meaningful evaluation of this rapidly spreading service technology is to be gleaned and response measures are to be put into effect.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 20
    Publication Date: 2015-08-21
    Description: This paper reports on a study of the modelling, validation and analysis of an integrated 1 MW (electrical output) tri-generation system energized by solar energy. The impact of local climatic conditions in the Mediterranean region on the system performance was considered. The output of the system that comprised a parabolic trough collector (PTC), an organic Rankine cycle (ORC), single-effect desalination (SED), and single effect LiBr-H2O absorption chiller (ACH) was electrical power, distilled water, and refrigerant load. The electrical power was produced by the ORC which used cyclopentane as working fluid and Therminol VP-1 was specified as the heat transfer oil (HTO) in the collectors with thermal storage. The absorption chiller and the desalination unit were utilize the waste heat exiting from the steam turbine in the ORC to provide the necessary cooling energy and drinking water respectively. The modelling, which includes an exergetic analysis, focuses on the performance of the solar tri-generation system. The simulation results of the tri-generation system and its subsystems were produced using IPSEpro software and were validated against experimental data which showed good agreement. The tri-generation system was able to produce about 194 Ton of refrigeration, and 234 t/day distilled water.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 21
    Publication Date: 2015-08-20
    Description: Battery energy storage systems (BESSs) have been widely used for microgrid control. Generally, BESS control systems are based on proportional-integral (PI) control techniques with the outer and inner control loops based on PI regulators. Recently, model predictive control (MPC) has attracted attention for application to future energy processing and control systems because it can easily deal with multivariable cases, system constraints, and nonlinearities. This study considers the application of MPC-based BESSs to microgrid control. Two types of MPC are presented in this study: MPC based on predictive power control (PPC) and MPC based on PI control in the outer and predictive current control (PCC) in the inner control loops. In particular, the effective application of MPC for microgrids with multiple BESSs should be considered because of the differences in their control performance. In this study, microgrids with two BESSs based on two MPC techniques are considered as an example. The control performance of the MPC used for the control microgrid is compared to that of the PI control. The proposed control strategy is investigated through simulations using MATLAB/Simulink software. The simulation results show that the response time, power and voltage ripples, and frequency spectrum could be improved significantly by using MPC.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 22
    Publication Date: 2015-08-21
    Description: The determinations of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, which also wastes too much time and manpower. To address this problem, we propose machine learning models including artificial neural networks (ANNs) and support vector machines (SVM) to predict the heat collection rate and heat loss coefficient without a direct determination. Parameters that can be easily obtained by “portable test instruments” were set as independent variables, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, final temperature and angle between tubes and ground, while the heat collection rate and heat loss coefficient determined by the detection device were set as dependent variables respectively. Nine hundred fifteen samples from in-service water-in-glass evacuated tube solar water heaters were used for training and testing the models. Results show that the multilayer feed-forward neural network (MLFN) with 3 nodes is the best model for the prediction of heat collection rate and the general regression neural network (GRNN) is the best model for the prediction of heat loss coefficient due to their low root mean square (RMS) errors, short training times, and high prediction accuracies (under the tolerances of 30%, 20%, and 10%, respectively).
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 23
    Publication Date: 2015-08-08
    Description: According to the increasing worldwide attention to energy and the environmental performance of the building sector, building energy demand should be minimized by considering all energy uses. In this regard, the development of building components characterized by proper values of thermal transmittance, thermal capacity, and radiative properties is a key strategy to reduce the annual energy need for the microclimatic control. However, the design of the thermal characteristics of the building envelope is an arduous task, especially in temperate climates where the energy demands for space heating and cooling are balanced. This study presents a novel methodology for optimizing the thermo-physical properties of the building envelope and its coatings, in terms of thermal resistance, capacity, and radiative characteristics of exposed surfaces. A multi-objective approach is adopted in order to optimize energy performance and thermal comfort. The optimization problem is solved by means of a Genetic Algorithm implemented in MATLAB®, which is coupled with EnergyPlus for performing dynamic energy simulations. For demonstration, the methodology is applied to a residential building for two different Mediterranean climates: Naples and Istanbul. The results show that for Naples, because of the higher incidence of cooling demand, cool external coatings imply significant energy savings, whereas the insulation of walls should be high but not excessive (no more than 13–14 cm). The importance of high-reflective coating is clear also in colder Mediterranean climates, like Istanbul, although the optimal thicknesses of thermal insulation are higher (around 16–18 cm). In both climates, the thermal envelope should have a significant mass, obtainable by adopting dense and/or thick masonry layers. Globally, a careful design of the thermal envelope is always necessary in order to achieve high-efficiency buildings.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 24
    Publication Date: 2015-08-08
    Description: In recent years, global climate change has altered precipitation patterns, causing uneven spatial and temporal distribution of precipitation that gradually induces precipitation polarization phenomena. Taiwan is located in the subtropical climate zone, with distinct wet and dry seasons, which makes the polarization phenomenon more obvious; this has also led to a large difference between river flows during the wet and dry seasons, which is significantly influenced by precipitation, resulting in hydrological drought. Therefore, to effectively address the growing issue of water shortages, it is necessary to explore and assess the drought characteristics of river systems. In this study, the drought characteristics of northern Taiwan were studied using the streamflow drought index (SDI) and Markov chains. Analysis results showed that the year 2002 was a turning point for drought severity in both the Lanyang River and Yilan River basins; the severity of rain events in the Lanyang River basin increased after 2002, and the severity of drought events in the Yilan River basin exhibited a gradual upward trend. In the study of drought severity, analysis results from periods of three months (November to January) and six months (November to April) have shown significant drought characteristics. In addition, analysis of drought occurrence probabilities using the method of Markov chains has shown that the occurrence probabilities of drought events are higher in the Lanyang River basin than in the Yilan River basin; particularly for extreme events, the occurrence probability of an extreme drought event is 20.6% during the dry season (November to April) in the Lanyang River basin, and 3.4% in the Yilan River basin. This study shows that for analysis of drought/wet occurrence probabilities, the results obtained for the drought frequency and occurrence probability using short-term data with the method of Markov chains can be used to predict the long-term occurrence probability of drought/wet events.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 25
    Publication Date: 2015-08-08
    Description: Proper lighting is vital to improve, from an artistic point of view, the surface expanse and decorative detailing of architectural heritage buildings considered valuable. When properly lit, monumental buildings can become to onlookers an essential part of the city. Nowadays, for design planners dealing with the improvement of buildings, whose architectural design should be valorized, the real challenge is to combine the lighting artistic requirements with scrupulous economic management in order to limit the energy demand and to respect the environment. For these reasons, this case study examines the lighting of the monumental façade and the cloister of St. Peter in Chains situated in the Faculty of Engineering of Sapienza University of Rome. The present lighting installation, characterized by metal halides, compact fluorescent and halogen lamps, is compared with an alternative scenario presenting LED lamps and scenographic lighting of the monumental façade. Such comparison is based on the evaluation of the lighting levels for different visual tasks and on energy and maintenance issues; the first analysis was performed through the software DIALux Evo 4.0, whereas the second was performed using ecoCALC. This study leads to the conclusion that the lighting levels of the solution presenting LED lamps are better than those of the present solution, and they comply with current standards. Finally, the higher costs of LED lamp installations and the scenographic lighting of the monumental façade are balanced by lower maintenance costs, with a payback period of seven years.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 26
    Publication Date: 2015-08-08
    Description: Customer expectations can be extremely nebulous. This research identifies the demographic segmentations and their respective expectations for the spa market. Interviews were conducted and a subsequent questionnaire was employed to gather the voice of the customer and assess the expectations of spa clientele. All of the data was collected from luxury spas in Hawaii, and consisted of respondents from all over the world. Results of the survey suggest that while men want more tangible benefits of a spa, women prefer the experiential qualities of peace and rejuvenation. Additionally, those of lower to middle income focus on the atmosphere more than wealthier clients, who are looking for more long term spa benefits, such as a more youthful appearance.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 27
    Publication Date: 2015-08-08
    Description: Any World Heritage Cultural Landscape requires a clear boundary for administration. One of the administrative goals is sustainability. There is no widely identified way to demarcate the boundary of a World Heritage Cultural Landscape. This paper aims to explore a methodology framework to provide a holistic perspective for demarcating boundaries for a World Heritage Cultural Landscape. Honghe Hani Rice Terraces (HHRT) in Yunnan Province is a new World Heritage Cultural Landscape in China. We use it as a research area to illustrate the methodology framework. The framework of methodology is constructed based on four scales of a human-environment system identified by Anne Buttimer. It is used to describe the level of the sustainability of local economy, social organization, natural environment and people’s understanding of the human-environment. Four types of boundaries were investigated in this area. They are the boundary of Malizhai River Basin, the boundary of local water-allocation organization, the boundary of the economic network and the perceptual boundary of the human-environment system. With a comprehensive perspective, we integrated the four types of boundaries to judge the boundary of the core area of HHRT by three criteria, they are: Environmental sustainability, social justice, and the ability to create a new human-environment system. We conclude that some parts of the boundary of the core area of HHRT do not fit the criteria of sustainable development.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 28
    Publication Date: 2015-08-12
    Description: A state-of-health (SOH) estimation method for electric vehicles (EVs) is presented with three main advantages: (1) it provides joint estimation of cell’s aging states in terms of power and energy (i.e., SOHP and SOHE)—because the determination of SOHP and SOHE can be reduced to the estimation of the ohmic resistance increase and capacity loss, respectively, the ohmic resistance at nominal temperature will be taken as a health indicator, and the capacity loss is estimated based on a mechanistic model that is developed to describe the correlation between resistance increase and capacity loss; (2) it has wide applicability to various ambient temperatures—to eliminate the effects of temperature on the resistance, another mechanistic model about the resistance against temperature is presented, which can normalize the resistance at various temperatures to its standard value at the nominal temperature; and (3) it needs low computational efforts for on-board application—based on a linear equation of cell’s dynamic behaviors, the recursive least-squares (RLS) algorithm is used for the resistance estimation. Based on the designed performance and validation experiments, respectively, the coefficients of the models are determined and the accuracy of the proposed method is verified. The results at different aging states and temperatures show good accuracy and reliability.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 29
    Publication Date: 2015-08-12
    Description: Producing domestic hot water (DHW) with a ground source heat pump (GSHP) is challenging due to the high temperature (HT) of DHW. There are many studies proving the better performance of cascade heat pumps compared to single-stage heat pumps when the difference between the condensing and the evaporation temperature is large. In this system approach study, different GSHP arrangements are described and computationally compared. A two-stage heat pump arrangement is introduced in which water tanks of the heating system are utilized for warming up the DHW in two stages. It is shown that the electricity consumption with this two-stage system is approximately 31% less than with the single-stage heat pump and 12% less than with the cascade system. Further, both low temperature (LT) and HT heat pumps can run alone, which is not common in cascade or other two-stage heat pumps. This is advantageous because the high loads of the space heating and DHW production are not simultaneous. Proper insulation of the DHW and recirculation pipe network is essential, and drying towel rails or other heating coils should be avoided when aiming for a high efficiency. The refrigerants in the calculations are R407C for the LT heat pump and R134a for the HT heat pump. Investment costs are excluded from calculations.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 30
    Publication Date: 2015-08-12
    Description: The growth economy imposes multiple crises on humanity and the natural world. To challenge this economic growth imperative, the degrowth movement emerges as a dissident response. Although within an economic growth perspective, payments for ecosystem services (PES) have also been proposed to attenuate the negative impacts of capitalism, as a redistributive mechanism that is claimed to deliver equitable conservation and sustainability. Degrowth has notably similar concerns, although it is inclined to argue against PES traditional ideologies and practices, which lead conservation to perceive nature within economic growth and market ideologies, diminishing the relationship between humans and nature. In spite of that, PES are becoming a strong trend in environmental governance. This paper attempts to examine whether PES are, and how they could be suitable for degrowth, through the lens of its main sources. In order to integrate PES and degrowth, it could require a PES reconceptualization. Although we assert that PES are not the most appropriate instrument for conservation, we argue that maybe PES could contribute to degrowth as a transition instrument toward fostering better practices. However, it is important to elucidate how they can be used and under which circumstances they could be appropriate.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 31
    Publication Date: 2015-08-12
    Description: This research paper aims at developing and applying a constructive weighting methodology for the elicitation of local stakeholders’ preferences regarding a set of sustainability evaluation criteria during the assessment of low-carbon energy technologies. The overall methodology has been applied and tested for the sustainability evaluation of selected low-carbon energy technologies in Europe from a local stakeholders’ perspective. The researchers applied a constructive weighting methodology based on different Multiple Criteria Analysis (MCA) techniques to test the consistency of stakeholders’ preferences. The methodology was piloted based on a small-scale European local stakeholders’ survey within the framework of Covenant CapaCITY, an Intelligent Energy Europe project that supports the development of Sustainable Energy Action Plans (SEAPs). It became evident that the local stakeholders who participated placed high priorities on aspects such as CO2eq emissions reduction, ecosystem damages reduction, and resilience to climate change during the evaluation of low-carbon energy technologies. Considering the overall energy technologies assessment, wind off-shore, solar PV, hydropower, and wind on-shore achieved the highest scores and better reflected the priorities of local stakeholders considering a large set of multiple sustainability criteria. The high number of criteria led to some inconsistencies of stakeholders’ preferences, confirming the need for consistency checks and/or combining different methods of preference elicitation.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 32
    Publication Date: 2015-08-12
    Description: In this study, we allocate Greenhouse gas (GHG) emissions of electricity transmission to the consumers. As an allocation basis, we introduce energy distance. Energy distance takes the transmission load on the electricity energy system into account in addition to the amount of electricity consumption. As a case study, we estimate regional GHG emissions of electricity transmission loss in Chile. Life cycle assessment (LCA) is used to estimate the total GHG emissions of the Chilean electric power system. The regional GHG emission of transmission loss is calculated from the total GHG emissions. We construct the network model of Chilean electric power grid as an undirected network with 466 nodes and 543 edges holding the topology of the power grid based on the statistical record. We analyze the total annual GHG emissions of the Chilean electricity energy system as 23.07 Mt CO2-eq. and 1.61 Mt CO2-eq. for the transmission loss, respectively. The total energy distance for the electricity transmission accounts for 12,842.10 TWh km based on network analysis. We argue that when the GHG emission of electricity transmission loss is estimated, the electricity transmission load should be separately considered. We propose network theory as a useful complement to LCA analysis for the complex allocation. Energy distance is especially useful on a very large-scale electric power grid such as an intercontinental transmission network.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 33
    Publication Date: 2015-08-12
    Description: Recently, as more people are concerned with the issues around environment protection, research about how to reduce carbon emissions has drawn increasing attention. Encouraging public transportation is an effective measure to reduce carbon emissions. However, overland public transportation does less to lower carbon because of the gradually increasing pressure of the urban road traffic. Therefore, the waterbus along the coast becomes a new direction of the urban public transport development. In order to optimize the operation plan of the waterbus, a bi-level model considering carbon emissions is proposed in this paper. In the upper-level model, a multiple objective model is established, which considers both the interests of the passengers and the operator while considering the carbon emissions. The lower-level model is a traffic model split by using a Nested Logit model. A NSGA-II (Non-dominated Sorting Genetic Algorithm-II) algorithm is proposed to solve the model. Finally, the city of Zhoushan is chosen as an example to prove the feasibility of the model and the algorithm. The result shows that the proposed model for waterbus operation optimization can efficiently reduce transportation carbon emissions and satisfy passenger demand at the same time.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 34
    Publication Date: 2015-08-15
    Description: Thermostatically controlled loads (TCLs), such as air conditioners (ACs), are important demand response resources—they have a certain heat storage capacity. A change in the operating status of an air conditioner in a small range will not noticeably affect the users’ comfort level. Load control of TCLs is considered to be equivalent to a power plant of the same capacity in effect, and it can significantly reduce the system pressure to peak load shift. The thermodynamic model of air conditioning can be used to study the aggregate power of a number of ACs that respond to the step signal of a temperature set point. This paper analyzes the influence of the parameters of each AC in the group to the indoor temperature and the total load, and derives a simplified control model based on the two order linear time invariant transfer function. Then, the stability of the model and designs its Proportional-Integral-Differential (PID) controller based on the particle swarm optimization (PSO) algorithm is also studied. The case study presented in this paper simulates both scenarios of constant ambient temperature and changing ambient temperature to verify the proposed transfer function model and control strategy can closely track the reference peak load shifting curves. The study also demonstrates minimal changes in the indoor temperature and the users’ comfort level.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 35
    Publication Date: 2015-08-15
    Description: In room–corridor building geometry, the corridor smoke temperature is of great importance to fire protection engineering as indoor fires occur. Theoretical analysis and a set of reduced-scale model experiments were performed, and a virtual fire model was proposed, to investigate the correlations between the maximum smoke temperature in corridors and the smoke temperature in rooms. The results show that the dimensionless virtual fire heat release rate (HRR) is characterized by quadratic-polynomial of the dimensionless smoke temperature in fire rooms. The dimensionless distance from a virtual fire source to the corridor ceiling varies linearly with the dimensionless smoke temperature in a room. Results of multiple regression indicate that, at the impingement area of virtual fire, the dimensionless maximum smoke temperature in corridors is only related to the dimensionless virtual fire HRR; in the non-impingement area of a virtual fire, the dimensionless maximum smoke temperature in corridors is a function of the dimensionless virtual fire HRR and dimensionless longitude distance. The viscosity and conduction exhibit an insignificant impact on the maximum temperature in the corridor. Through replacing the parameters of virtual fire with the dimensionless smoke temperature in fire rooms, the correlations between dimensionless maximum temperature in corridors and the dimensionless smoke temperature in fire rooms were proposed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 36
    Publication Date: 2015-08-15
    Description: Changes in agriculture, including simultaneous intensification and abandonment, have significantly shaped the evolution of rural areas. The assessment of resilience in agricultural systems could provide insights into the ability of many rural areas to survive and regain competitiveness following disturbances. The aim of this study is to use the adaptive cycle heuristic as a diagnostic tool to study dynamics of change in two agricultural sectors (durum wheat/sheep and goat farming) in the Basilicata region of Southern Italy over the last seventy years. The heuristic was applied through a participatory approach in a community of stakeholders who have conceived, in collaboration with researchers, the Manifesto “Let’s Think Basilicata” as a regional instrument of analysis and a laboratory of ideas and development of proposals. Despite some methodological difficulties, the adaptive cycle heuristic proved useful to describe processes of change in the socio-ecological system and could have enormous potential in shaping policy instruments for rural areas. However, much greater research is needed, both in terms of theory and methodology, before policy impacts on resilience in socio-ecological systems can be fully understood.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 37
    Publication Date: 2015-08-15
    Description: In developing countries, the drinking water supply is still an open issue. In sub-Saharan Africa, only 68% of the population has access to improved sources of drinking water. Moreover, some regions are affected by geogenic contaminants (e.g., fluoride and arsenic) and the lack of access to sanitation facilities and hygiene practices causes high microbiological contamination of drinking water in the supply chain. The Water Safety Plan (WSP) approach introduced by the World Health Organisation (WHO) in 2004 is now under development in several developing countries in order to face up to these issues. The WSP approach was elaborated within two cooperation projects implemented in rural areas of Burkina Faso and Senegal by two Italian NGOs (Non-Governmental Organisations). In order to evaluate its sustainability, a questionnaire based on five different sustainability elements and a cost and time consumption evaluation were carried out and applied in both the case studies. Results demonstrated that the questionnaire can provide a useful and interesting overview regarding the sustainability of the WSP; however, further surveys in the field are recommended for gathering more information. Time and costs related to the WSP elaboration, implementation, and management were demonstrated not to be negligible and above all strongly dependent on water quality and the water supply system complexity.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 38
    Publication Date: 2015-08-15
    Description: The development of cities has always had a very close relation with water. However, cities directly impact land use patterns and greatly change natural landscapes, aggravating floods. Considering this situation, this paper intends to discuss lowland occupation and city sustainability in what regards urban stormwater management, fluvial space, and river restoration, aiming at minimizing flood risks and improving natural and built environment conditions. River plains tend to be attractive places for a city to grow. From ancient times, levees have been used to protect lowland areas along major watercourses to allow their occupation. However, urban rivers demand space for temporary flood storage. From a systemic point of view, levees along extensive river reaches act as canalization works, limiting river connectivity with flood plains, rising water levels, increasing overtopping risks and transferring floods downstream. Departing from this discussion, four case studies in the Iguaçu-Sarapuí River Basin, a lowland area of Rio de Janeiro State, Brazil, are used to compose a perspective in which the central point refers to the need of respecting watershed limits and giving space to rivers. Different aspects of low-lying city planning are discussed and analyzed concerning the integration of the built and natural environments.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 39
    Publication Date: 2015-08-18
    Description: With the microgrid revolution, each house will have the ability to meet its own energy needs locally from renewable energy sources such as solar or wind. However, real-time data gathering, energy management and control of renewable energy systems will depend mainly on the performance of the communications infrastructure. This paper describes the design of a communication network architecture using both wired and wireless technologies for monitoring and controlling distributed energy systems involving small-scale wind turbines and photovoltaic systems. The proposed communication architecture consists of three layers: device layer, network layer, and application layer. Two scenarios are considered: a smart-house and a smart-building. Various types of sensor nodes and measurement devices are defined to monitor the condition of the renewable energy systems based on the international electrotechnical commission standard. The OPNET Modeler is used for performance evaluation in terms of end-to-end (ETE) delay. The network performance is compared in view of ETE delay, reliability and implementation cost for three different technologies: Ethernet-based, WiFi-based, and ZigBee-based.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 40
    Publication Date: 2015-08-06
    Description: In this paper, we present the results of an economic feasibility study and propose a system structure to test and maintain electrical stability. In addition, we present real operation results after constructing a remote microgrid on an island in South Korea. To perform the economic feasibility study, a commercial tool called HOMER was used. The developed remote microgrid consists of a 400 kW wind turbine (WT) generator, 314 kW photovoltaic (PV) generator, 500 kVA × 2 grid forming inverter, 3 MWh lithium ion battery, and an energy management system (EMS). The predicted renewable energy fraction was 91% and real operation result was 82%. The frequency maintaining rate of the diesel power plants was 57% but the remote microgrid was 100%. To improve the operating efficiency of the remote microgrid, we investigated the output range of a diesel generator.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 41
    Publication Date: 2015-08-06
    Description: Low energy X-ray fluorescence (XRF) and soft X-ray absorption (XAS) microspectroscopies at high space-resolution are employed for the investigation of the coelectrodeposition of composites consisting of a polypyrrole(PPy)-matrix and Mn-based ternary dispersoids, that have been proposed as promising electrocatalysts for oxygen-reduction electrodes. Specifically, we studied Mn–Co–Cu/PP, Mn–Co–Mg/PPy and Mn–Ni–Mg/PPy co-electrodeposits. The Mn–Co–Cu system features the best ORR electrocatalytic activity in terms of electron transfer number, onset potential, half-wave potential and current density. XRF maps and micro-XAS spectra yield compositional and chemical state distributions, contributing unique molecular-level information on the pulse-plating processes. Mn, Ni, Co and Mg exhibit a bimodal distribution consisting of mesoscopic aggregates of micrometric globuli, separated by polymer-rich ridges. Within this common qualitative scenario, the individual systems exhibit quantitatively different chemical distribution patterns, resulting from specific electrokinetic and electrosorption properties of the single components. The electrodeposits consist of Mn3+,4+-oxide particles, accompanied by combinations of Co0/Co2+, Ni0/Ni2+ and Cu0,+/Cu2+ resulting from the alternance of cathodic and anodic pulses. The formation of highly electroactive Mn3+,4+ in the as-fabricated material is a specific feature of the ternary systems, deriving from synergistic stabilisation brought about by two types of bivalent dopants as well as by galvanic contact to elemental metal; this result represents a considerable improvement in material quality with respect to previously studied Mn/PPy and Mn-based/PPy binaries.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 42
    Publication Date: 2015-08-06
    Description: The countries of the Gulf Cooperation Council (GCC) have both large fossil fuel resources and vast renewable energy potentials. Here, we investigate in a literature meta-analysis and a survey, whether there is a need for renewables in the GCC, what barriers and risks presently deter investments, and what possible policy-solutions could be. We find that there is a long-term need for renewables, to diversify the economy and prepare for a post-fossil fuel era. In the short term, two main obstacles deter investments: inefficient bureaucracy, and the combination of fossil fuel/electricity subsidies and the absence of renewable energy support. Removing fossil fuel and consumption subsidies or introducing a support scheme could make investments in renewables profitable. Eliminating energy subsidies appears particularly beneficial to the economic outlook but this seems particularly difficult to implement, due to the political economy of rentier states. Increased bureaucratic transparency and efficiency is needed, so that potentially attractive investments can rapidly and predictably obtain the necessary permissions. Hence, the administrative and economic environment for renewable energy investments in the GCC is not right today, and no breakthrough is on the horizon, but there is a range of policy solutions to enable investments in the future.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 43
    Publication Date: 2015-08-06
    Description: This study was conducted to develop an artificial neural network (ANN)-based prediction model that can calculate the amount of cooling energy during the setback period of accommodation buildings. By comparing the amount of energy needed for diverse setback temperatures, the most energy-efficient optimal setback temperature could be found and applied in the thermal control logic. Three major processes that used the numerical simulation method were conducted for the development and optimization of an ANN model and for the testing of its prediction performance, respectively. First, the structure and learning method of the initial ANN model was determined to predict the amount of cooling energy consumption during the setback period. Then, the initial structure and learning methods of the ANN model were optimized using parametrical analysis to compare its prediction accuracy levels. Finally, the performance tests of the optimized model proved its prediction accuracy with the lower coefficient of variation of the root mean square errors (CVRMSEs) of the simulated results and the predicted results under generally accepted levels. In conclusion, the proposed ANN model proved its potential to be applied to the thermal control logic for setting up the most energy-efficient setback temperature.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 44
    Publication Date: 2015-08-06
    Description: The non-uniform surface temperature distribution of a battery cell results from complex reactions inside the cell and makes efficient thermal management a challenging task. This experimental work attempts to determine the evolution of surface temperature distribution of three pouch type commercial cells: Nickel Manganese Cobalt oxide (NMC)-based 20 Ah cell, Lithium Iron Phosphate (LFP) 14 Ah, and Lithium Titanate Oxide (LTO) 5 Ah battery cell by using contact thermistor and infrared (IR) thermography. High current (up to 100 A) continuous charge/discharge and high current (80 A) micro pulse cycling profile were applied on the cells. It was found that thermistor based temperature profile varied cell to cell, especially the LTO cell. Among the investigated cells, the NMC cell shows highest temperature rise and the LTO cell the lowest rise. IR (Infrared) images revealed the spatial distribution of surface temperature, in particular the location of the hottest region varies depending not only on the geometrical and material properties of the cell, but also the type of loads applied on the cells. Finally, a modeling perspective of the cell temperature non-uniformity is also discussed.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 45
    Publication Date: 2015-08-07
    Description: A novel metal borohydride ammonia-borane complex Ca(BH4)2·NH3BH3 is characterized as the decomposition product of the recently reported perovskite-type metal borohydride NH4Ca(BH4)3, suggesting that ammonium-based metal borohydrides release hydrogen gas via ammonia-borane-complexes. For the first time the concept of proton-hydride interactions to promote hydrogen release is applied to a cation-anion pair in a complex metal hydride. NH4Ca(BH4)3 is prepared mechanochemically from Ca(BH4)2 and NH4Cl as well as NH4BH4 following two different protocols, where the synthesis procedures are modified in the latter to solvent-based ball-milling using diethyl ether to maximize the phase yield in chlorine-free samples. During decomposition of NH4Ca(BH4)3 pure H2 is released, prior to the decomposition of the complex to its constituents. As opposed to a previously reported adduct between Ca(BH4)2 and NH3BH3, the present complex is described as NH3BH3-stuffed α-Ca(BH4)2.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 46
    Publication Date: 2015-08-08
    Description: In 2007, the EU established challenging goals for all Member States with the aim of obtaining 20% of their energy consumption from renewables, and offshore wind is expected to be among the renewable energy sources contributing highly towards achieving this target. Currently wind turbines are designed for a 25-year service life with the possibility of operational extension. Extending their efficient operation and increasing the overall electricity production will significantly increase the return on investment (ROI) and decrease the levelized cost of electricity (LCOE), considering that Capital Expenditure (CAPEX) will be distributed over a larger production output. The aim of this paper is to perform a detailed failure mode identification throughout the service life of offshore wind turbines and review the three most relevant end of life (EOL) scenarios: life extension, repowering and decommissioning. Life extension is considered the most desirable EOL scenario due to its profitability. It is believed that combining good inspection, operations and maintenance (O&M) strategies with the most up to date structural health monitoring and condition monitoring systems for detecting previously identified failure modes, will make life extension feasible. Nevertheless, for the cases where it is not feasible, other options such as repowering or decommissioning must be explored.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 47
    Publication Date: 2015-06-04
    Description: The distribution automation system (DAS) is vulnerable to cyber-attacks due to the widespread use of terminal devices and standard communication protocols. On account of the cost of defense, it is impossible to ensure the security of every device in the DAS. Given this background, a novel quantitative vulnerability assessment model of cyber security for DAS is developed in this paper. In the assessment model, the potential physical consequences of cyber-attacks are analyzed from two levels: terminal device level and control center server level. Then, the attack process is modeled based on game theory and the relationships among different vulnerabilities are analyzed by introducing a vulnerability adjacency matrix. Finally, the application process of the proposed methodology is illustrated through a case study based on bus 2 of the Roy Billinton Test System (RBTS). The results demonstrate the reasonability and effectiveness of the proposed methodology.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 48
    Publication Date: 2015-06-04
    Description: We analysed the environmental impacts of three biogas systems based on dairy manure, sorghum and maize. The geographical scope of the analysis is the Po valley, in Italy. The anaerobic digestion of manure guarantees high GHG (Green House Gases) savings thanks to the avoided emissions from the traditional storage and management of raw manure as organic fertiliser. GHG emissions for maize and sorghum-based systems, on the other hand, are similar to those of the Italian electricity mix. In crop-based systems, the plants with open-tank storage of digestate emit 50% more GHG than those with gas-tight tanks. In all the environmental impact categories analysed (acidification, particulate matter emissions, and eutrophication), energy crops based systems have much higher impacts than the Italian electricity mix. Maize-based systems cause higher impacts than sorghum, due to more intensive cultivation. Manure-based pathways have always lower impacts than the energy crops based pathways, however, all biogas systems cause much higher impacts than the current Italian electricity mix. We conclude that manure digestion is the most efficient way to reduce GHG emissions; although there are trade-offs with other local environmental impacts. Biogas production from crops; although not providing environmental benefits per se; may be regarded as an option to facilitate the deployment of manure digestion.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 49
    Publication Date: 2015-06-04
    Description: As the world moves toward greenhouse gas reduction, there is increasingly active work around Li-ion chemistry-based batteries as an energy source for electric vehicles (EVs), hybrid electric vehicles (HEVs) and smart grids. In these applications, the battery management system (BMS) requires an accurate online estimation of the state of charge (SOC) in a battery pack. This estimation is difficult, especially after substantial battery aging. In order to address this problem, this paper utilizes SOC estimation of Li-ion battery packs using a fuzzy-improved extended Kalman filter (fuzzy-IEKF) for Li-ion cells, regardless of their age. The proposed approach introduces a fuzzy method with a new class and associated membership function that determines an approximate initial value applied to SOC estimation. Subsequently, the EKF method is used by considering the single unit model for the battery pack to estimate the SOC for following periods of battery use. This approach uses an adaptive model algorithm to update the model for each single cell in the battery pack. To verify the accuracy of the estimation method, tests are done on a LiFePO4 aged battery pack consisting of 120 cells connected in series with a nominal voltage of 432 V.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 50
    Publication Date: 2015-06-04
    Description: The sustainability of a small-scale self-consumption wood-energy chain for heat generation in central Italy was analyzed from a technical, economic and energetic point of view. A micro-chain was developed within the CRA-ING farm at Monterotondo (Rome, Italy): The purpose of this system was to produce biomass for supplying a heating plant within the CRA-ING property as a substitute for diesel fuel. A poplar short rotation coppice, established with clones AF2, AF6 and Monviso, fed the micro-chain. The rotation was biennial. The average plantation production (Mgd.m.·ha−1·year−1) was 10.2, with a maximum of 13.53 for the twin-rows AF2 and a minimum of 8.00 for the single-row Monviso. The economic assessment was based on the Net Present Value (NPV) method and the equivalent annuity cost, and found an average saving of 15.60 €·GJ−1 of heat generated by the wood chips heating system in comparison with the diesel heating system over a 10 year lifetime of the thermal power plant. The energy assessment of the poplar plantation, carried out using the Gross Energy Requirements method, reported an energy output/input ratio of 12.3. The energy output/input ratio of the whole micro-chain was 4.5.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 51
    Publication Date: 2015-06-04
    Description: Natural gas is becoming increasingly important as a primary energy source. A suitable replacement for fossil natural gas is bio-SNG, produced by biomass gasification, followed by methanation. A major challenge is efficient gas cleaning processes for removal of sulfur compounds and other impurities. The present study focuses on development of a gas cleaning step for a product gas produced in a 50 MWfuel gasification system. The developed gas cleaning washing process is basically a modification of the Rectisol process. Several different process configurations were evaluated using Aspen plus, including PC-SAFT for the thermodynamic modeling. The developed configuration takes advantage of only one methanol wash column, compared to two columns in a conventional Rectisol process. Results from modeling show the ability of the proposed configuration to remove impurities to a sufficiently low concentrations - almost zero concentration for H2S, CS2, HCl, NH3 and HCN, and approximately 0.01 mg/Nm3 for COS. These levels are acceptable for further upgrading of the gas in a methanation process. Simultaneously, up to 92% of the original CO2 is preserved in the final cleaned syngas stream. No process integration or economic consideration was performed within the scope of the present study, but will be investigated in future projects to improve the overall process.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 52
    Publication Date: 2015-06-04
    Description: Cool roof coatings have a beneficial impact on reducing the heat load of a range of building types, resulting in reduced cooling energy loads. This study seeks to understand the extent to which cool roof coatings could be used as a residential demand side management (DSM) strategy for retrofitting existing housing in a constrained network area in tropical Australia where peak electrical demand is heavily influenced by residential cooling loads. In particular this study seeks to determine whether simulation software used for building regulation purposes can provide networks with the ‘impact certainty’ required by their DSM principles. The building simulation method is supported by a field experiment. Both numerical and experimental data confirm reductions in total consumption (kWh) and energy demand (kW). The nature of the regulated simulation software, combined with the diverse nature of residential buildings and their patterns of occupancy, however, mean that simulated results cannot be extrapolated to quantify benefits to a broader distribution network. The study suggests that building data gained from regulatory simulations could be a useful guide for potential impacts of widespread application of cool roof coatings in this region. The practical realization of these positive impacts, however, would require changes to the current business model for the evaluation of DSM strategies. The study provides seven key recommendations that encourage distribution networks to think beyond their infrastructure boundaries, recognising that the broader energy system also includes buildings, appliances and people.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 53
    Publication Date: 2015-06-04
    Description: The European Union and its Member States are seeking to decarbonize their energy systems, including the electricity sector and, at the same time, pursue market integration. However, renewable energy (RE) deployment and the liberalization of the energy-only market have raised concerns at the national level about the security of electricity supplies in the future. Some actors consider the lack of sufficient investments in generation capacities a threat to supply security. As a consequence, it was proposed that capacity markets solve these problems. The underlying assumption is that the market design is the only determining factor for investments in security of supply options. In this article, we question this narrow view and identify further determinants of the investment decisions of electricity market participants. Based on the insights of institutional sociology and economics, we understand the market to be a social institution that structures the behavioural expectations of market participants. Derived from the theoretical conceptualization and based on qualitative literature review and own work, we find four determinants for investment behaviour beyond the formal market design: Material opportunities, strategic actor behavior and identity, focusing events and discursive expectations about the future. With this perspective, we discuss the introduction of a European Energy Union as a possible tool that might have a great impact on the more informal determinants such as expectations about the future and the construction of a European energy narrative.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 54
    Publication Date: 2015-06-05
    Description: In this paper, an asymmetrical fuzzy-logic-control (FLC)-based maximum power point tracking (MPPT) algorithm for photovoltaic (PV) systems is presented. Two membership function (MF) design methodologies that can improve the effectiveness of the proposed asymmetrical FLC-based MPPT methods are then proposed. The first method can quickly determine the input MF setting values via the power–voltage (P–V) curve of solar cells under standard test conditions (STC). The second method uses the particle swarm optimization (PSO) technique to optimize the input MF setting values. Because the PSO approach must target and optimize a cost function, a cost function design methodology that meets the performance requirements of practical photovoltaic generation systems (PGSs) is also proposed. According to the simulated and experimental results, the proposed asymmetrical FLC-based MPPT method has the highest fitness value, therefore, it can successfully address the tracking speed/tracking accuracy dilemma compared with the traditional perturb and observe (P&O) and symmetrical FLC-based MPPT algorithms. Compared to the conventional FLC-based MPPT method, the obtained optimal asymmetrical FLC-based MPPT can improve the transient time and the MPPT tracking accuracy by 25.8% and 0.98% under STC, respectively.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 55
    Publication Date: 2015-06-05
    Description: Adhesion (cohesion) and agglomeration properties of gas hydrate particles have been a key to hydrate management in flow assurance in natural gas pipelines. Despite its importance, the relevant data in the area, such as the surface energy and the interfacial energy of gas hydrates with gas and/or water, are scarce; presumably due to the experimental difficulties involved in the measurements. Here we review what is known about the surface energy and the interfacial energy of gas hydrates to date. In particular, we ask a question as to whether pre-melting can occur on the surface of gas hydrates. Surface thermodynamic analyses show that pre-melting is favoured to occur on the surface of gas hydrates, however, not sufficient data are available to assess its thickness. The effects of the existence of pre-melting layers on the cohesion and friction forces between gas hydrate particles are also discussed.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 56
    Publication Date: 2015-06-06
    Description: During the last few years, Italian dairy farms, which gather, process and sell milk at the national level, have strengthened their leading market position at the detriment of dairy cooperatives, operating within regional borders. Moreover, decreasing milk prices and increasing production costs have recently induced many farmers to open automatic vending machines, dispensing raw milk for direct sale to local consumers. In order to contribute to the environmental assessment of alternative systems, this study estimated CO2 emissions related to the transport from production farms to point of sale, for three brands of fresh milk currently sold in the Umbria region (Italy), starting from the food miles indicator as a simple concept, easily understood by consumers. These brands differ in the origin of milk (national, regional and local) and distribution channels (large-scale retail channels for national and regional brands and vending machines for the local one). Thus, we estimated the emissions generated by the transport of the fresh milk consumed by regional households. In agreement with previous studies about CO2 emissions of foreign milk supply chains, the analysis showed that the production system of regional-branded milk, sold by retail channels, is the most efficient in terms of the environmental impact of transport.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 57
    Publication Date: 2015-06-06
    Description: The need and estimated utility for a structured analysis of the Roşia Montană gold exploitation project have been palpable in the Romanian public sphere during the last 15 years and there is a vast amount of conflicting information and opinions on the benefits and risks involved. This article provides a comprehensive decision analysis of the Roşia Montană project. Over 100 documents from the past years have been gathered regarding the Roşia Montană mining project, which cover the main official, formal and less formal documents covering the case and produced by a wide range of stakeholders. These were then analyzed while designing a multi-criteria tree including the relevant perspectives under which the most commonly discussed four alternatives were analyzed. The result of this can be translated into a valuable recommendation for the mining company and for the political decision-makers. If these stakeholders want the continuation of the project and its acceptance by civil society, the key challenge is to increase the transparency of the process and improve the credibility and legal aspects; if these aspects cannot be met, the decision-makers need to pay attention to the alternatives available for a sustainable development in the area.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 58
    Publication Date: 2015-06-09
    Description: The dehydriding process and hydrogen–deuterium exchange (H–D exchange) of xLiBH4 + (1 − x)Mg2FeD6 (x = 0.25, 0.75) composites has been studied in detail. For the composition with x = 0.25, only one overlapping mass peak of all hydrogen and deuterium related species was observed in mass spectrometry. This implied the simultaneous dehydriding of LiBH4 and Mg2FeD6, despite an almost 190 °C difference in the dehydriding temperatures of the respective discrete complex hydrides. In situ infrared spectroscopy measurements indicated that H–D exchange between [BH4]− and [FeD6]4− had occurred during ball-milling and was promoted upon heating. The extent of H–D exchange was estimated from the areas of the relevant mass signals: immediately prior to the dehydriding, more than two H atoms in [BH4]− was replaced by D atoms. For x = 0.75, H–D exchange also occurred and about one to two H atoms in [BH4]− was replaced by D atoms immediately before the dehydriding. In contrast to the situation for x = 0.25, firstly LiBH4 and Mg2FeD6 dehydrided simultaneously with a special molar ratio = 1:1 at x = 0.75, and then the remaining LiBH4 reacted with the Mg and Fe derived from the dehydriding of Mg2FeD6.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 59
    Publication Date: 2015-08-04
    Description: Energy storage devices are expected to be more frequently implemented in wind farms in near future. In this paper, both pumped hydro and fly wheel storage systems are used to assist a wind farm to smooth the power fluctuations. Due to the significant difference in the response speeds of the two storages types, the wind farm coordination with two types of energy storage is a problem. This paper presents two methods for the coordination problem: a two-level hierarchical model predictive control (MPC) method and a single-level MPC method. In the single-level MPC method, only one MPC controller coordinates the wind farm and the two storage systems to follow the grid scheduling. Alternatively, in the two-level MPC method, two MPC controllers are used to coordinate the wind farm and the two storage systems. The structure of two level MPC consists of outer level and inner level MPC. They run alternatively to perform real-time scheduling and then stop, thus obtaining long-term scheduling results and sending some results to the inner level as input. The single-level MPC method performs both long- and short-term scheduling tasks in each interval. The simulation results show that the methods proposed can improve the utilization of wind power and reduce wind power spillage. In addition, the single-level MPC and the two-level MPC are not interchangeable. The single-level MPC has the advantage of following the grid schedule while the two-level MPC can reduce the optimization time by 60%.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 60
    Publication Date: 2015-08-04
    Description: Electric machines play an important role in modern energy conversion systems. This paper presents a novel brushless fault-tolerant flux-modulated memory (FTFM) machine, which incorporates the merits of a flux-modulated permanent magnet machine and multi-phase memory machine and is very suitable for applications that require wide speed ranges of constant-power operation. Due to the magnetic modulation effect, the FTFM machine can produce a large torque at relatively low speeds. Due to the usage of aluminum-nickel-cobalt (AlNiCo) magnets, this machine can readily achieve a flexible air-gap flux controllability with temporary DC current pulses. Consequently, the constant-power region is effectively expanded, and the machine\'s efficiency during constant-power operation is increased. Due to the multi-phase armature winding design, the FTFM machine enables lower torque ripple, increased fault tolerance ability and a higher possibility of splitting the machine power through a higher number of phases, thus the per-phase converter rating can be reduced. The design methodology and working principle of this kind of machine are discussed. The electromagnetic performances of the proposed machine are analyzed using the time-stepping finite element method (TS-FEM).
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 61
    Publication Date: 2015-08-05
    Description: The purpose of this paper is to investigate combustion characteristics for rotary engine via numerical studies. A 3D numerical model was developed to study the influence of several operative parameters on combustion characteristics. A novel rotary engine called, “Leaf Spring Rotary Engine”, was used to illustrate the structure and principle of the engine. The aims are to (1) improve the understanding of combustion process, and (2) quantify the influence of rotational speed, excess air ratio, initial pressure and temperature on combustion characteristics. The chamber space changed with crankshaft rotation. Due to the complexity of chamber volume, an equivalent modeling method was presented to simulate the chamber space variation. The numerical simulations were performed by solving the incompressible, multiphase Unsteady Reynolds-Averaged Navier–Stokes Equations via the commercial code FLUENT using a transport equation-based combustion model; a realizable  turbulence model and finite-rate/eddy-dissipation model were used to account for the effect of local factors on the combustion characteristics.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 62
    Publication Date: 2015-08-05
    Description: We propose an ethical analysis as a method to reflect on how companies’ decisions promote sustainable development. The method proceeds by first identifying the choice according to financial business interests, and by then scrutinizing this choice according to consequentialist and deontological ethics. The paper applies the method to the choice of an Environmental Impact Assessment (EIA) that a consortium of Brazilian companies (EGASUR) delivered as part of their project proposal for the realization of the Inambari hydropower dam in the Peruvian Amazon. We show that if an EIA is chosen based on the attempt to maximize the financial bottom line, it raises ethical issues both from a consequentialist perspective by involving negative consequences for various stakeholder groups, and from a deontological perspective by not complying with relevant rules, guidelines, and principles. The two ethical perspectives hence reveal where the consortium faces impediments to a genuine commitment to sustainability. Building on stakeholder interviews, observations of the project developments, and the executive summary of the actual EIA, we provide indications that EGASUR has indeed made a choice that resembles a decision based on financial interests.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 63
    Publication Date: 2015-08-06
    Description: An accurate assessment of a building’s wall performance, defined through the thermal transmittance, is essential to compute the annual energy consumption. Analyzing opaque surfaces, the heat transfer across walls can be modeled by an electro-thermal analogy, based on resistors series, crossed by a one-dimensional heat flow. This analogy is well established and it refers to stratigraphy composed of homogeneous materials. When dealing with inhomogeneous materials, possibly including hollow bricks, the wall’s thermal transmittance is evaluated by means of an effective conductance. However, in order to verify the theoretical models effectiveness, a comparison with in situ measurements is needed. In this paper, three building walls characterized by different stratigraphy have been analyzed; by employing a heat flow meter investigation. Measurements results and estimated thermal transmittance values—calculated applying the standard UNI EN ISO 6946—have been compared.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 64
    Publication Date: 2015-08-06
    Description: With an increased awareness of sustainability issues, natural ventilation has become an elegant method for reducing the costs and environmental effects of the energy that is used to maintain comfortable indoor air quality rather than using mechanical ventilation. The windows in many industrial buildings are continuously open to exhaust pollutants and intake fresh air. Though windows are functional and efficient for natural ventilation, rainwater is able to penetrate through the windows during wind-driven rain. For industries in which the moisture content affects the quality of the product, the intrusion of a large amount of rainwater through windows must be prevented without compromising the effective ventilation. The aim of this research is to determine an innovative design for windows to accomplish the optimum of high ventilation and low rain penetration. For this purpose, windows are variously innovated and tested in full-scale measurements, reduced-scale wind-tunnel measurements and computational fluid dynamics (CFD). An artificial rain and wind velocity to mimic the average of the maximum values in Korea are created. The maximum reduction in rain penetration of over 98% compared to basic 90° open windows is attained with only a 4%–9% decrement of ventilation efficiency in the two recommended designs.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 65
    Publication Date: 2015-08-06
    Description: The tree-growing sector is considered to be an important supplier of food and raw material for industry worldwide. Increasingly competitive decisions regarding international investment in orchards depend on business analysis. This study compares three apple orchards situated in Cluj-Napoca, on the Eastern limits of the Transylvanian Plain, Romania. While the climatic and soil conditions are relatively consistent among the three orchards, the technical and economic results (expressed in hectares) vary due to the use of three different technological systems of apple production: extensive, intensive, and super-intensive. The study compares the life cycle, starting with age of fructification, production level (quantity and quality), costs (investment and production costs—divided into material costs, mechanical costs, human costs, and overhead costs), income, profit (including rate of profit), and investment efficiency: Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PP). It was observed that the most economically efficient technological system in terms of investments is the super-intensive one, with a higher production level, a higher share of Extra Class apples, and a younger age of initial fructification. However certain inconveniences of this system—such as a more expensive investment, a higher cost of running the business throughout the year, and a reduced life cycle—cannot be ignored.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 66
    Publication Date: 2015-08-08
    Description: The efficiency of wireless power transfer is sensitive to the horizontal and vertical distances between the transmitter and receiver coils due to the magnetic coupling change. To address the output voltage variation and efficiency drop caused by misalignment, a uniform voltage gain frequency control is implemented to improve the power delivery and efficiency of wireless power transfer under misalignment. The frequency is tuned according to the amplitude and phase-frequency characteristics of coupling variations in order to maintain a uniform output voltage in the receiver coil. Experimental comparison of three control methods, including fixed frequency control, resonant frequency control, and the proposed uniform gain control was conducted and demonstrated that the uniform voltage gain control is the most robust method for managing misalignment in wireless charging applications.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 67
    Publication Date: 2015-08-08
    Description: Water table control has been successfully tested to improve the sustainability of water management in cranberry production. In the province of Québec (Canada), three sites were investigated to determine the optimum water table depth below soil surface (WTD) using three criteria: (1) increasing yield without decreasing fruit quality; (2) minimizing the amount of water needed by the sprinkler system; and (3) avoiding hypoxic stresses in the rhizosphere. Our results show that the final yield, the berry sugar content, the total number of berries, the number of berries per upright, and the fruit set were maximized when the WTD was 60 cm. Sprinkler water savings of 77% were obtained where the WTD was shallower than 66 cm. In order to avoid hypoxic conditions due to poor drainage, the water level in the canals surrounding the beds should be lowered to 80 cm when a rainfall or a frost protection irrigation is anticipated. All sides of a block of beds must be surrounded by canals to ensure a uniform WTD and to avoid lateral hydraulic gradients that could cause peripheral seepage losses.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 68
    Publication Date: 2015-08-08
    Description: Effective change order management is very important in maintaining the financial sustainability of various stakeholders related to construction projects by minimizing cost overruns. In this study, we propose a zero-cost risk management approach based on the collar option model in order to control for the loss caused by change orders, the main cause of cost overruns in construction projects. We apply this model to actual projects for empirical analysis. The analysis, based on 237 projects, indicates that insurance buyers benefit from the collar option model in 46% of the cases, while insurance sellers do so in 53% of the cases. In most cases, the insurance buyer is the owner. According to the model, the owner experiences a loss when the cost overrun caused by change orders is lower than what was expected. In such cases, it is appropriate to conclude that the loss is not caused by the collar option model, but by the absence of additional revenue. However, the insurance seller suffers a loss if the cost overrun is higher than the strike price of the call option. Thus, the insurance seller needs to have expertise in construction management.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 69
    Publication Date: 2015-08-08
    Description: This study aimed to investigate the influence of the service encounter expectations of senior customers during wellness tours on customer satisfaction. The organizational attributes of hotels, organizational characteristics and employee characteristics, were adopted as mediating variables. A total of 346 valid questionnaires were retrieved from 50 year-old and above seniors in Taiwan. The results showed that the service encounter expectations of seniors had an indirect influence on customer satisfaction and the organizational attributes mediated the service encounter expectations of seniors and customer satisfaction. The moment of truth in the interactions between service staff members and seniors represents the pivotal management implication of this study.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 70
    Publication Date: 2015-08-08
    Description: In higher education there is a growing demand for graduates with the competence to transform our society toward a sustainable future. Part of this competence in sustainability is anticipatory competence, the ability to engage with multiple futures, manage uncertainty and hold a worldview that the future can and should be steered toward a more just sustainable path. In order to further examine and operationalise anticipatory competence, a course “Sustainability and the Future” was developed and run in the University of Vechta, Germany, as part of an action research cycle exploring key competencies for sustainability in higher education. Reflective journaling was used to explore the competence acquisition process along with focus groups with students after the course. The analysis of this programme shows that while certain subject areas such as values, transport and population models provoke more critical reflection on the future, skills such as the ability to work with emotional aspects of the future, for instance hope, were perceived to be necessary for anticipatory competence.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 71
    Publication Date: 2015-08-13
    Description: Smart cards are able to store and protect relatively large amounts of data. When applied in universities, they can act as multi-purpose, multi-function and smart ID cards. This would avoid the waste of resources and maintain environmental sustainability. This study proposes a model that integrates Technology Acceptance Model and Theory of Reasoned Action into a framework incorporating the notion of environmental concern in order to explore the factors that affect students’ behavioral intention to use University Smart Cards. This study employs a quantitative method for primary data collection via a structured questionnaire for university students. The findings indicated that the perceived usefulness and subjective norm of university smart card systems have the most significant predictive power on potential users’ attitudes and intentions of adopting the card.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 72
    Publication Date: 2015-08-13
    Description: Electric vehicle (EV) energy consumption is variable and dependent on a number of external factors such as road topology, traffic, driving style, ambient temperature, etc. The goal of this paper is to detect and quantify correlations between the kinematic parameters of the vehicle and its energy consumption. Real-world data of EV energy consumption are used to construct the energy consumption calculation models. Based on the vehicle dynamics equation as underlying physical model, multiple linear regression is used to construct three models. Each model uses a different level of aggregation of the input parameters, allowing predictions using different types of available input parameters. One model uses aggregated values of the kinematic parameters of trips. This model allows prediction with basic, easily available input parameters such as travel distance, travel time, and temperature. The second model extends this by including detailed acceleration data. The third model uses the raw data of the kinematic parameters as input parameters to predict the energy consumption. Using detailed values of kinematic parameters for the prediction in theory increases the link between the statistical model and its underlying physical principles, but requires these parameters to be available as input in order to make predictions. The first two models show similar results. The third model shows a worse fit than the first two, but has a similar accuracy. This model has great potential for future improvement.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 73
    Publication Date: 2015-08-15
    Description: Energy saving, reduction of greenhouse gasses and increased use of renewables are key policies to achieve the European 2020 targets. In particular, distributed renewable energy sources, integrated with spatial planning, require novel methods to optimise supply and demand. In contrast with large scale wind turbines, small and medium wind turbines (SMWTs) have a less extensive impact on the use of space and the power system, nevertheless, a significant spatial footprint is still present and the need for good spatial planning is a necessity. To optimise the location of SMWTs, detailed knowledge of the spatial distribution of the average wind speed is essential, hence, in this article, wind measurements and roughness maps were used to create a reliable annual mean wind speed map of Flanders at 10 m above the Earth’s surface. Via roughness transformation, the surface wind speed measurements were converted into meso- and macroscale wind data. The data were further processed by using seven different spatial interpolation methods in order to develop regional wind resource maps. Based on statistical analysis, it was found that the transformation into mesoscale wind, in combination with Simple Kriging, was the most adequate method to create reliable maps for decision-making on optimal production sites for SMWTs in Flanders (Belgium).
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 74
    Publication Date: 2015-08-15
    Description: Tourism is perceived as an appropriate solution for pursuing sustainable economic growth due to its main characteristics. In the context of sustainable tourism, gamification can act as an interface between tourists (clients), organisations (companies, NGOs, public institutions) and community, an interface built in a responsible and ethical way. The main objective of this study is to identify gamification techniques and applications used by organisations in the hospitality and tourism industry to improve their sustainable activities. The first part of the paper examines the relationship between gamification and sustainability, highlighting the links between these two concepts. The second part identifies success stories of gamification applied in hospitality and tourism and reviews gamification benefits by analysing the relationship between tourism organisations and three main tourism stakeholders: tourists, tourism employees and local community. The analysis is made in connection with the main pillars of sustainability: economic, social and environmental. This study is positioning the role of gamification in the tourism and hospitality industry and further, into the larger context of sustainable development.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 75
    Publication Date: 2015-08-15
    Description: Traditional rural landscapes emerged from the long term interaction of the natural and anthropogenic environment. These landscapes are now threatened by drastic social-ecological changes. Recent international trends on sustaining cultural landscapes place great emphasis on understanding of multiple values, presented in the landscape, by considering various stakeholder perspectives. It is now recognized that strong community engagement with the landscape should be translated into conservation and management practices. This paper aims to examine the recent conservation activities around endangered traditional rural landscapes in Korea through a case study of Gacheon village. In this village, since 2000, a series of central administrative measures have been implemented to revive the local community, and to conserve its distinctive landscape. By analyzing challenges to the site, by discussing conservation experience and lessons, and by recommending future strategies for sustaining its cultural landscapes, this paper is expected to provide a basis for future policy-making for safeguarding traditional rural landscapes.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 76
    Publication Date: 2015-08-11
    Description: Metal hydrides can be utilized for hydrogen storage and for thermal energy storage (TES) applications. By using TES with solar technologies, heat can be stored from sun energy to be used later, which enables continuous power generation. We are developing a TES technology based on a dual-bed metal hydride system, which has a high-temperature (HT) metal hydride operating reversibly at 600–800 °C to generate heat, as well as a low-temperature (LT) hydride near room temperature that is used for hydrogen storage during sun hours until there is the need to produce electricity, such as during night time, a cloudy day or during peak hours. We proceeded from selecting a high-energy density HT-hydride based on performance characterization on gram-sized samples scaled up to kilogram quantities with retained performance. COMSOL Multiphysics was used to make performance predictions for cylindrical hydride beds with varying diameters and thermal conductivities. Based on experimental and modeling results, a ~200-kWh/m3 bench-scale prototype was designed and fabricated, and we demonstrated the ability to meet or exceed all performance targets.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 77
    Publication Date: 2015-08-08
    Description: Greenhouse gas emissions have serious impacts on the natural environment. Therefore, the restrictions imposed on carbon emission force enterprises to take carbon emission into consideration when making production decisions. In this paper, in the context of allowing emission trading and investment of emission reduction technology, models were presented for a two-stage supply chain to analyze the optimal investment and pricing decisions. The results indicate that manufacturer’s endurance capacity of reduction difficulty is higher in the cooperation model than in the Stackelberg game model, and that perfect coordination of supply chains can be realized by a revenue sharing contract. From the perspective of a consumer, low-carbon products mean higher price, so that subsidies or tax exemptions should be provided to keep low prices. Meanwhile, the government can promote investment in emission-reduction technologies and achieve its emission reduction targets by controlling emission trading price, strengthening emission reduction publicity and providing technology investment subsidies.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 78
    Publication Date: 2015-08-08
    Description: Electronic paper (e-paper) is a major sector of Taiwan’s Optoelectronic industry. It has paid much attention on the development of flexible displays. Even though the market is booming, the future is still unclear for business development. No research has yet forecasted the future market size of the e-paper industry. In addition, proposing an appropriate forecasting model to understand the trend of this industry plays a crucial role for market players and government’s authorities in formulating correct strategies. Therefore, in this paper, the future market size of Taiwan’s e-paper industry is predicted by an effective combined grey model. Two combinations of DGM(2,1) and Verhulst model with Fourier series and Markov chain, namely FM-Verhulst and FMDGM(2,1), were presented. Based on the annual data of Taiwan’s e-paper industry, the results show that the forecasting performances of two FM-Verhulst and FMDGM(2,1) models are highly accurate compared with other grey models. Precision is 96.36% and 97.77%, respectively. However, for long-term prediction, the FMDGM(2,1) model obtains the best performance in all proposed grey models. With obtained forecasting results in Taiwan’s e-paper industry by the FMDGM(2,1) model, it can be pointed out that the future market size of Taiwan’s e-paper would slowly increase in the next few years.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 79
    Publication Date: 2015-08-08
    Description: ising global energy needs and limited fossil fuel reserves have led to increased use of renewable energies. In Germany, this has entailed massive exploitation of agricultural biomass for biogas generation, associated with unsustainable farming practices. Organic agriculture not only reduces negative environmental impacts, organic farmers were also prime movers in anaerobic digestion (AD) in Germany. This study’s aim was to identify the structure, development, and characteristics of biogas production associated with organic farming systems in order to estimate further development, as well as energetic and associated agronomic potentials. Surveys were conducted among organic farms with AD technology. 144 biogas plants could be included in the analysis. Total installed electrical capacity was 30.8 MWel, accounting for only 0.8% of the total installed electrical capacity in the German biogas sector. Recently, larger plant types (>250 kWel) with increased use of (also purchased) energy crops have emerged. Farmers noticed increases in yields (22% on average) and quality of cash crops in arable farming through integrated biogas production. In conclusion, although the share of AD in organic farming is relatively small it can provide various complementary socio-ecological benefits such as the enhancement of food output through digestate fertilization without additional need for land, while simultaneously reducing greenhouse gas emissions from livestock manures and soils. However, to achieve this eco-functional intensification, AD systems and their management have to be well adapted to farm size and production focus and based primarily on residue biomass.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 80
    Publication Date: 2015-08-08
    Description: Research from a variety of disciplines suggests that online technologies (i.e., Web 2.0 and social media) have considerable potential for spurring proenvironmental action; however, relatively little work examines how to effectively capitalize on these communication and organization tools. This review paper describes the Technologies for Proenvironmental Action Model (TPAM), a conceptual framework that explicates how different functions of Web 2.0 and social media (i.e., informational, relational, and experiential) can generate and/or facilitate personal, social, and contextual pathways to environmentally responsible behaviors. As derived from the TPAM, the likelihood of achieving practical goals of increasing proenvironmental behaviors is enhanced when technological functions are matched to the different pathways to proenvironmental action. For example, the relational function of technologies, as exemplified by Social Networking Sites (SNSs), should be particularly effective in communicating social norms supportive of environmentally responsible behaviors. The TPAM is intended as a guide to develop novel approaches, research questions, and methodologies in leveraging Web 2.0 and social media technologies to promote proenvironmental action. Results will contribute to basic theory development and work in applied settings (e.g., local environmental organizations) in order to effectively communicate and organize with different segments of the population to increase sustainable behaviors.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 81
    Publication Date: 2015-08-13
    Description: Sustainability reports are tools for disseminating information to stakeholders and the public, serving the organizations in the dual purpose of communicating CSR and being accountable. The production of these reports has recently become more prevalent in the food industry, despite the fact this practice has received heavy criticism on two fronts: The quality of the tool for communication, and the extent of accountability. In addition to these criticisms, organizations must overcome the additional challenge of publishing sustainability reports that successfully meet the demands of a multi-stakeholder audience. In light of the importance of this practice, this paper presents a method to assess the communication and accountability characteristics of Spanish food companies’ sustainability reports. This method is based on the method Analytic Network Process (ANP) and adopts a multi-stakeholder approach. This research, therefore, provides a reference model for improving sustainability reports, with the aim of successfully meeting their communication objectives and the demands of all stakeholders.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 82
    Publication Date: 2015-08-13
    Description: This research is the first attempt of a carbon emission investigation of tourism-based farms. A total of 36 cases were investigated. The result reveals that each tourist returns an average revenue of 28.6 USD and generates an average 10.9 kg-CO2eq per visit of carbon emissions. The average carbon emission density for each land area is 8.2 t/ha·year and is 245 kg/m²·year for each floor area. It is estimated that the overall carbon emissions reach 321,751 tons annually. The tourism-based farms were clustered into five categories, based on their business characteristics. It was found that high-end vacation leisure farms produce 2.46 times the carbon emissions than natural eco-conservation farms. Carbon emissions were 42% higher than the annual average in July and August. A secondary high season is in February, but it is merely higher than the annual average by 8% because of the mild climate. Two significant models for predicting carbon emissions were constructed by stepwise regression. As agriculture administrative authorities in Taiwan gradually have begun admitting the cultivated lands for multi-purpose usage, tourism-based farms have been increasing drastically. This study provides references for both public authorities and farm managers in exploring the issues with regard to carbon emissions and farm sustainability.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 83
    Publication Date: 2015-08-14
    Description: Assessing the performance or energy efficiency of a single construction element by itself is often a futile exercise. That is not the case, however, when an element is designed, among others, to improve building energy performance by harnessing renewable energy in a process that requires a source of external energy. Harnessing renewable energy is acquiring growing interest in Mediterranean climates as a strategy for reducing the energy consumed by buildings. When such reduction is oriented to lowering demand, the strategy consists in reducing the building’s energy needs with the use of construction elements able to passively absorb, dissipate, or accumulate energy. When reduction is pursued through M&E services, renewable energy enhances building performance. The efficiency of construction systems that use renewable energy but require a supplementary power supply to operate can be assessed by likening these systems to regenerative heat exchangers built into the building. The indicators needed for this purpose are particularly useful for designers, for they can be used to compare the efficiency or performance to deliver an optimal design for each building. This article proposes a series of indicators developed to that end and describes their application to façades bearing phase change materials (PCMs).
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 84
    Publication Date: 2015-08-14
    Description: In the provinces of north China, combined heat and electric power generations (CHP) are widely utilized to provide both heating source and electricity. While, due to the constraint of thermal-electric coupling within CHP, a mass of wind turbines have to offline operate during heating season to maintain the power grid stability. This paper proposes a thermal-electric decoupling (TED) approach to release the energy waste. Within the thermal-electric decoupling system, heat storage and electric boiler/heat pump are introduced to provide an auxiliary thermal source during hard peak shaving period, thus relying on the participation of an outside heat source, the artificial electric power output change interval could be widened to adopt more wind power and reduce wind power curtailment. Both mathematic models and methods are proposed to calculate the evaluation indexes to weight the effect of TED, by using the Monte Carlo simulation technique. Numerical simulations have been conducted to demonstrate the effectiveness of the proposed methods, and the results show that the proposed approach could relieve up to approximately 90% of wind power curtailment and the ability of power system to accommodate wind power could be promoted about 32%; moreover, the heating source is extended, about 300 GJ heat could be supplied by TED during the whole heating season, which accounts for about 18% of the total heat need.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 85
    Publication Date: 2015-08-14
    Description: The metropolitan city of Istanbul is becoming overcrowded and the demand for clean water is steeply rising in the city. The use of analytical approaches has become more and more critical for forecasting the water supply and demand balance in the long run. In this research, Istanbul’s water supply and demand data is collected for the period during 2006 and 2014. Then, using an autoregressive integrated moving average (ARIMA) model, the time series water supply and demand forecasting model is constructed for the period between 2015 and 2018. Three important sustainability metrics such as water loss to supply ratio, water loss to demand ratio, and water loss to residential demand ratio are also presented. The findings show that residential water demand is responsible for nearly 80% of total water use and the consumption categories including commercial, industrial, agriculture, outdoor, and others have a lower share in total water demand. The results also show that there is a considerable water loss in the water distribution system which requires significant investments on the water supply networks. Furthermore, the forecasting results indicated that pipeline projects will be critical in the near future due to expected increases in the total water demand of Istanbul. The authors suggest that sustainable management of water can be achieved by reducing the residential water use through the use of water efficient technologies in households and reduction in water supply loss through investments on distribution infrastructure.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 86
    Publication Date: 2015-08-15
    Description: Most studies explored green-roof thermal effects on a few hot summer days based on short-term monitoring data. Few studies investigated the seasonal and diurnal patterns of thermal performance and associated weather effects. This research aims to address the following two questions: (1) how green-roof thermal performance varies with different season and time; and (2) to what extent can thermal performance be predicted by background weather parameters? A retrofitted extensive green roof was established on the top of a railway station in subtropical Hong Kong. Monitoring data covering a two-year period, one year before roof greening and one year after, were collected and analyzed. Results indicated notable seasonal and diurnal patterns of green-roof thermal performance. It exhibited cooling effects in spring, summer and fall, but warming effects in winter. The cooling effects were more pronounced in summer than spring and fall, on sunny days than rainy and cloudy days, and in nighttime than daytime. Air temperature, relative humidity, wind speed, solar radiation, and soil moisture could explain 83.6%–86% of the thermal effects’ variation. The multiple-regression models based on the five weather variables established in this study provide an uncomplicated and direct approach to predict the thermal performance of similar extensive green roofs in subtropical areas.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 87
    Publication Date: 2015-09-10
    Description: The study presents a cost effective electricity generation portfolio for six island states for a 20-year period (2015–2035). The underlying concept investigates whether adding sizeable power capacities of renewable energy sources (RES) options could decrease the overall costs and contribute to a more sustainable, indigenous electricity generation at the same time. Often, island states rely on fossil fuels which, apart from dependence on foreign resources, also includes an additional, significant transport cost. This is an extra motive to study the extent in which island states represent primary locations for RES technologies. For the aims of the present study an optimization model has been developed and following numerous runs the obtained results show that installing PV and battery capacities can delay-reduce the huge investments in fossil options in early periods. Thus, investment on RES can have a positive, long-term effect on the overall energy mix. This prompt development can happen without adding new subsidies but there is a need to address the existing socio-economic barriers with intelligent design of financing and economic instruments and capacity building as discussed in the conclusions.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 88
    Publication Date: 2015-09-11
    Description: We have developed a visualized 3-D model of a City Sustainability Index (CSI) based on our original concept of city sustainability in which a sustainable city is defined as one that maximizes socio-economic benefits while meeting constraint conditions of the environment and socio-economic equity on a permanent basis. The CSI is based on constraint and maximization indicators. Constraint indicators assess whether a city meets the necessary minimum conditions for city sustainability. Maximization indicators measure the benefits that a city generates in socio-economic aspects. When used in the policy-making process, the choice of constraint indicators should be implemented using a top-down approach. In contrast, a bottom-up approach is more suitable for defining maximization indicators because this technique involves multiple stakeholders (in a transdisciplinary approach). Using different materials of various colors, shapes, sizes, we designed and constructed the visualized physical model of the CSI to help people evaluate and compare the performance of different cities in terms of sustainability. The visualized model of the CSI can convey complicated information in a simple and straightforward manner to diverse stakeholders so that the sustainability analysis can be understood intuitively by ordinary citizens as well as experts. Thus, the CSI model helps stakeholders to develop critical thinking about city sustainability and enables policymakers to make informed decisions for sustainability through a transdisciplinary approach.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 89
    Publication Date: 2015-09-12
    Description: This study examines the factors that influence individual intentions towards the adoption of full electric vehicles. A sample including 308 respondents was collected on the streets of Macau. The collected data were analysed by confirmatory factor analysis and structural equation modelling. The results demonstrate that environmental concerns and the perception of environmental policy are antecedent factors of the perception of full electric vehicles, which influences the behavioural intention to purchase full electric vehicles. This study also finds that the perception of economic benefit is one of the key factors influencing the adoption of full electric vehicles. Vehicle operators seek economic benefits from future long-term fuel savings, high energy efficiency, and cheap electricity. Thus, a government striving to promote low-carbon transportation needs to scale up its efforts to enhance citizens’ environmental concerns and to establish proper environmental policy as well as to provide long-term financial and strategic support for electric vehicles.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 90
    Publication Date: 2015-09-12
    Description: Building owners are encouraged to reduce energy use in order to both contribute to national energy-saving goals and reduce the costs of heating and operation. It is important to choose the most optimal renovation measures available so as to achieve cost-effective energy use while maintaining excellent indoor environments, without sacrificing architectural quality or negatively affecting the environment. Building owners and managers often have neither the time nor the expertise required to properly evaluate the available renovation options before making a final decision. Renovation measures are often calculated to repay investments in a short time, rather than taking into account life-cycle costs (LCC), despite the fact that a thoughtful, comprehensive renovation is often more cost-effective in the long run. This paper presents a systematic approach for evaluating different renovation alternatives based on a number of sustainability criteria. The methodology has been verified using three multi-family apartment buildings in Sweden. The benefit of using the proposed methodology is made clear through a comparison between the different renovation alternatives from a sustainability perspective, and will hopefully serve as encouragement to choose renovation measures which involve marginally increased investments but lead to significant environmental and social benefits in the long-term.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 91
    Publication Date: 2015-09-12
    Description: A survey was conducted of the wastewater treatment systems and related sludge handling practices on the island of Yap, in the Federated States of Micronesia, to assist in identifying areas where further work would be merited to improve on effectiveness and sustainability. A detailed inventory was made of communal septic tanks as found at health centers and schools. Though most of these septic tanks appeared to be functional, there were concerns due to some units being positioned within the tidal zone, covered over with vegetation, or out of reach of the pump truck. Furthermore, the centralized wastewater treatment plant on Yap provides only primary treatment consisting of a limited removal of suspended solids. Thus, only partially treated sewage is being discharged to the bay. Excess sludge is drawn from the treatment plant on a quarterly basis, which local farmers regularly make use of as fertilizer for crop application without adequate treatment. As an immediate target for further study and pilot testing, exploring the use of an attached-growth process as an inexpensive retrofit to enhance the effectiveness of the treatment plant is proposed. In addition, the benefits of implementing a composting program for recycle of waste sludge in a safe manner and developing a framework for management of septic tanks are discussed.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 92
    Publication Date: 2015-09-12
    Description: Soil degradation is a global problem caused by many factors including excessive tillage, inappropriate crop rotations, excessive grazing or crop residue removal, deforestation, mining, construction and urban sprawl. To meet the needs of an expanding global population, it is essential for humankind to recognize and understand that improving soil health by adopting sustainable agricultural and land management practices is the best solution for mitigating and reversing current soil degradation trends. This research editorial is intended to provide an overview for this Special Issue of Sustainability that examines the global problem of soil degradation through reviews and recent research studies addressing soil health in Africa, Australia, China, Europe, India, North and South America, and Russia. Two common factors—soil erosion and depletion of soil organic matter (SOM)—emerge as consistent indicators of how “the thin layer covering the planet that stands between us and starvation” is being degraded. Soil degradation is not a new problem but failing to acknowledge, mitigate, and remediate the multiple factors leading to it is no longer a viable option for humankind. We optimistically conclude that the most promising strategies to mitigate soil degradation are to select appropriate land uses and improve soil management practices so that SOM is increased, soil biology is enhanced, and all forms of erosion are reduced. Collectively, these actions will enable humankind to “take care of the soil so it can take care of us”.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 93
    Publication Date: 2015-09-12
    Description: Urban development bestows a great opportunity to increase sustainability in the built environment as cities are responsible for the majority of environmental impacts. However, the urban development process is fragmented and sub-optimization leads to unsustainable life cycle outcomes. The purpose of this study is to examine the urban development process from a life cycle perspective and identify how different actors understand life cycle management. By utilizing an inductive qualitative research design, 38 in-depth thematic interviews were conducted within the Finnish urban development industry including a case study and independent interviews from different phases of the urban development life cycle. The theoretical perspective is a combination of the ecosystem construct and life cycle management. Results show that there is no clear responsible actor for life cycle management in urban development. All actors claim that there is value to be added, mostly in economic, but also environmental and social terms. This study reveals that investors should be the responsible actor in the urban development process. By claiming responsibility and focusing on life cycle leadership we can improve sustainability in urban development, and respond to the urban sustainability challenge, thus improving the quality of life and welfare in our urban society.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 94
    Publication Date: 2015-09-12
    Description: Compared with previous studies that have focused on customers’ behavioral intentions or the factors that influence purchase behaviors on blogs or discussion boards, in this study, we examine the factors of independent food blogs or discussion boards that influence users’ customer citizenship behaviors. Six food blogs were selected based on the flow rate and food diaries. 323 Subjects were chosen from the blog user population and then interviewed to develop the data needed for this study. The results indicate that psychological needs, customer satisfaction, and customer-company identification positively affect customer citizenship behaviors. High satisfaction of customer-orientation is a critical management strategy on food blogs. This study adapts physically existing organizational behavior theory through appropriate inference and modification for virtual community. Unlike past studies that focused on customer purchase intention, this study emphasizes customer value and social media of the virtual community.
    Electronic ISSN: 2071-1050
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 95
    Publication Date: 2015-09-17
    Description: In recent years, water (R718) as a kind of natural refrigerant—which is environmentally-friendly, safe and cheap—has been reconsidered by scholars. The systems of using water as the refrigerant, such as water vapor compression refrigeration and heat pump systems run at sub-atmospheric pressure. So, the research on water boiling heat transfer at sub-atmospheric pressure has been an important issue. There are many research papers on the evaporation of water, but there is a lack of data on the characteristics at sub-atmospheric pressures, especially lower than 3 kPa (the saturation temperature is 24 °C). In this paper, the experimental research on water boiling heat transfer on a horizontal copper rod surface at 1.8–3.3 kPa is presented. Regression equations of the boiling heat transfer coefficient are obtained based on the experimental data, which are convenient for practical application.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 96
    Publication Date: 2015-09-17
    Description: The dual-permanent-magnet-excited (DPME) machine employs permanent magnets (PMs) both on the stator and the rotor. It relies on the bi-directional field modulation effect (BFME) to achieve stable electromechanical energy conversion. Therefore, this new type of machine is capable of offering much higher torque capability than its traditional counterparts. This paper is devoted to investigating the optimum design method for improving the BFME of DPME machines, so as to further improve their produced electromagnetic torques. Response surface methodology is engaged to investigate the impacts of shape factors of the stator and rotor slots on the torque capability of the DPME machine, and the fitted models are built up by using both the finite element method (FEM) and the least-squares method. After that, the optimum shape factors are obtained from the fitted models. The results estimated by using both two-dimensional (2D)-FEM and three-dimensional (3D)-FEM demonstrate that the pull-out torque of the optimum case is 24.5% larger than that of the initial case, while the usage of PM material of the optimum case is 8.9% less than that of the initial case.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 97
    Publication Date: 2015-09-17
    Description: In this study, driving data for various types of drivers are collected using a VIDE (virtual integrated driving environment), and a driver model is developed. To represent the driver tendencies quantitatively, the DDA (degree of driver aggression) is proposed based on fuzzy logic. DDA has a 0-1 value; the closer the DDA is to one, the more aggressive the driver. Using the DDA, an engine on/off and battery charging power control algorithm are developed to improve the fuel economy of a power-split-type plug-in hybrid electric vehicle. The engine on/off control reduces the frequent engine on/off caused by aggressive driving, whereas the battery charging power control maintains the battery state of charge (SOC) by operating the engine according to the DDA. It is found that the proposed control algorithm improves fuel economy by 17.3% compared to the existing control for an aggressive driver.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 98
    Publication Date: 2015-09-17
    Description: This paper describes the Experimental Power Grid Centre (EPGC) microgrid test facility, which was developed to enable research, development and testing for a wide range of distributed generation and microgrid technologies. The EPGC microgrid facility comprises a integrated electrical and thermal grid with a flexible and configurable architecture, and includes various distributed energy resources and emulators, such as generators, renewable, energy storage technologies and programmable load banks. The integrated thermal grid provides an opportunity to harness waste heat produced by the generators for combined heat, power and cooling applications, and support research in optimization of combined electrical-thermal systems. Several case studies are presented to demonstrate the testing of different control and operation strategies for storage systems in grid-connected and islanded microgrids. One of the case studies also demonstrates an integrated thermal grid to convert waste heat to useful energy, which thus far resulted in a higher combined energy efficiency. Experiment results confirm that the facility enables testing and evaluation of grid technologies and practical problems that may not be apparent in a computer simulated environment.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 99
    Publication Date: 2015-09-17
    Description: Paraffin fuel has been found to have a regression rate that is higher than conventional HTPB (hydroxyl-terminated polybutadiene) fuel and, thus, presents itself as an ideal energy source for a hybrid rocket engine. The energy characteristics of paraffin-based fuel and HTPB fuel have been calculated by the method of minimum free energy. The thermal degradation characteristics were measured for paraffin, pretreated paraffin, HTPB and paraffin-based fuel in different working conditions by the using differential scanning calorimetry (DSC) and a thermogravimetric analyzer (TGA). The regression rates of paraffin-based fuel and HTPB fuel were tested by a rectangular solid-gas hybrid engine. The research findings showed that: the specific impulse of paraffin-based fuel is almost the same as that of HTPB fuel; the decomposition temperature of pretreated paraffin is higher than that of the unprocessed paraffin, but lower than that of HTPB; with the increase of paraffin, the initial reaction exothermic peak of paraffin-based fuel is reached in advance, and the initial reaction heat release also increases; the regression rate of paraffin-based fuel is higher than the common HTPB fuel under the same conditions; with the increase of oxidizer mass flow rate, the regression rate of solid fuel increases accordingly for the same fuel formulation.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 100
    Publication Date: 2015-09-17
    Description: This work reports results related to the “EU-FP7-HRC-Power” project aiming at developing micro-meso hybrid sources of power. One of the goals of the project is to achieve surface temperatures up to more than 1000 K, with a ∆T ≤ 100 K, in order to be compatible with a thermal/electrical conversion by thermo-photovoltaic cells. The authors investigate how to reach that goal adopting swirling chambers integrated in a thermally-conductive and emitting element. The converter consists of a small parallelepiped brick inside two separated swirling meso-combustion chambers, which heat up the parallelepiped, emitting material by the combustion of H2 and air at ambient pressure. The overall dimension is of the order of cm. Nine combustion simulations have been carried out assuming detailed chemistry, several length/diameter ratios (Z/D = 3, 5 and 11) and equivalence ratios (0.4, 0.7 and 1); all are at 400 W of injected chemical power. Among the most important results are the converter surfaces temperatures, the heat loads, provided to the environment, and the chemical efficiency. The high chemical efficiency, h > 99.9%, is due to the relatively long average gas residence time coupled with the fairly good mixing due to the swirl motion and the impinging air/fuel jets that provide heat and radicals to the flame.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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