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This paper presents the application of the Discrete Event Simulation (DES) in an industrial plant to analyze the behavior of the consumption and generation of electrical energy in conjunction with other variables of the process. In other words, the process modeling was conducted considering the energy consumption in equipment as well as the local photovoltaic (PV) energy generation. A medium-sized plant was the reference base used herein, and the main variables considered were the time of supply of tanks and processing of raw material, active power of equipment and energy tariffs. A simulation model with resolution in seconds was designed, enabling the simulation of consumption curves of each equipment of a given part of the production process. The equipment of variable active demand was modeled by a mathematical regression method, and the others were assumed with constant power. The same model was altered to unit in minutes for simulating the monthly electricity consumption, so as to obtain financial results. The contractual rules for electricity supply were included, and the use of a diesel-powered generator was taken into account. The application of a freeware was employed as a low cost alternative for small and medium-sized companies, even though the lack of graphic resources has increased the complexity of the system modeling process. The model with resolution in seconds proved to be efficient to simulate the consumption profile of a specific equipment that alters the power in a short-time period, such as the pumps. The model, on the other hand, in minutes allowed a more effective analysis in terms of finance, enabling the verification of alternative scenarios throughout a month. The monthly cost reduction perceived by considering self-generation in this model was about 36%. Detailed diagram of the main elements of modeling of a manufacturing process of an industry concentrating on the consumption and generation of electric energy. Image 1 • The electricity consumption in an industrial process can be approached in a simulation model. • PV energy can be simulated together with variables of industrial processes. • The discrete event simulation can be used in industrial processes to optimize the electricity management. [ABSTRACT FROM AUTHOR]

Since the prices of oil and gasoline increase, the wind power will become increasingly competitive. So, one should present the safe conclusions with respect to the economic viability in terms of investment and operation of the wind turbines at a given location. Egypt enjoys fully a high potentiality of wind energy and its applications, nevertheless the study of this renewable source is still below the required level. Technical assessment of a two wind farms of 300 MW installed capacity has been presented on the proposed locations, where the correct roughness factor was estimated and the rate of wind power density potential per month at 100 m altitude has been derived. Frequency distributions, monthly capacity factor and annual full load hours have been investigated to choose the best suitable wind turbines over there. Annual capacity factors are high ranged between 44% and 42%, respectively, that represents 3855 h of annual operation hours in Kharga station, while 3680 of operative yearly hours were at Dakhla South station. The considered wind farms could generate 1130 GWh of electricity per year. Average cost per kWh is around 2 € cent. In terms of practical economic analysis and considerations given in this paper, Kharga and Dakhla South sites are global areas for wind power plants and have the ability to generate electricity with low price. Also, it is lower than the local electricity tariff in Egypt, which was generated by other ways through the fiscal year 2017/2018, that is equivalent to 5.4 US cent per kilowatt-hour. As a result, this great amount of electricity produced from this venture is relatively more than the needs of Egypt and can be exported to Southern European countries on the Mediterranean Sea, that will reduce the domestic fossil fuel consumption and create a clean regional climate by preventing thousands of tons of carbon emissions per year. • Proposed wind farms will generate energy 1,130 GWh/year. • Annual capacity factors are high ranged between 44% and 42%. • Economical wind applications are possible in the two sites. • The expected cost varies in the range of 1.96–2.09 € cents/kWh. [ABSTRACT FROM AUTHOR]

Growing environmental awareness and the relevance of energy costs in many industries has led to the need of improving energy efficiency in operations management; hence, energy-aware scheduling (EAS) has grown in importance. In EAS three basic strategies can be identified. First, a large part of research activities is aimed at reducing energy consumption ; second, energy costs can be reduced by making use of varying energy prices ; third, a rarely-examined aspect is load curve leveling , used to reduce demand charges or grid utilization charges. In this paper, all three strategies are integrated into one model for the first time in order to solve a multi-objective hybrid flow shop scheduling problem. A new multiphase iterated local search algorithm (ILS) is developed to determine a three-dimensional Pareto front regarding three objectives: makespan, total energy costs and peak load. Tabu lists, several time- and energy-dependent list scheduling algorithms, a right-shifting procedure and a reference point based fitness function enable high-quality solutions. A computational study is presented that analyzes the interdependencies of objectives and compare the proposed algorithm to well-known NSGA2 heuristic. The ILS is proven to be suitable in purposeful search in the solution space, which allows practical decision support. [ABSTRACT FROM AUTHOR]

for energy efficiency (DfEE) is highly valued in improving the energy efficiency during product use and the decisions with a significant impact on the product's energy-efficiency performance are made during early design stages. The product's design features determined in early design stages are hierarchical in nature and the design process for new products is generally top-down. However, current DfEE methods tend to firstly improve the design features on the bottom level and then the higher level till the energy-efficiency target is achieved. The contradiction between the top-down design process and the bottom-up energy-efficiency improvement severely limits the innovation in new product design and hinders the emergence of highly energy-efficient products. In addition, the energy-efficiency improvement is divergent and can generate a large number of solutions, but the design process needs to be convergent and arrives at a few or a single best solution. This paper proposes a top-down DfEE method called three-step cyclic design method for new product development in early design stages. It is based on a spiral design process and a three-layer framework of DfEE activities. The former supports a top-down approach for energy-efficiency improvement, and the latter ensures a convergent DfEE process. The implementation of this method is detailed through a case study of a wind turbine. [ABSTRACT FROM AUTHOR]

Abstract Low-carbon energy retrofitting in buildings plays an important role because 75% of European buildings are considered inefficient and more than 40% are currently over 50 years old. The economic reinvestment of energy retrofit actions through reduced energy bills, as energy directives promote, greatly depends upon the energy consumption patterns. In support of the decision-making process towards a low-carbon energy transition in multi-family buildings, this paper introduces a novel assessment method that evaluates the profitability of energy efficiency measures, according to standard operating conditions derived from energy performance certificate procedures and real occupant energy consumption scenarios, through a parametric analysis. The aim is to assess the real energy and economic savings of retrofitting actions, depending on different energy-related occupant scenarios, and to enable comparisons with other buildings, providing a valuable model to identify the most feasible and low-carbon energy strategies in residential energy retrofitting. A Spanish multi-family building from 1942 is taken as the reference case study. The results show that energy savings for dwellings vary up to 80%, and the net present value per dwelling differs by up to 20,000€ between different energy consumption patterns. The most appropriate energy efficiency measures according to low, medium or high consumption scenarios are highlighted. Highlights • Novel method to support the decision-making process in energy retrofitting. • A parametric analysis is made based on different energy consumption patterns. • Consumption profiles based on standard conditions and real behaviour of occupants. • Energy saving and return on investment are evaluated for each consumption scenario. • The method fulfils two main purposes of official procedures from energy directives. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a novel topology of a hybrid energy storage system (HESS) and an improved energy distribution control strategy for four-wheel independent-drive electric vehicles (4WIDEVs) to improve their energy efficiency and dynamic performance under urban driving conditions. The small 4WIDEV was developed for only urban driving conditions and was limited to a maximum speed of 60 km/h. The HESS consists of a battery, four ultracapacitor (UC) groups and five direct current/direct current (DC/DC) converters. The 4 UC groups of the proposed HESS have two connection modes under braking conditions, namely a series-connected recovery structure (SCRS) and a parallel-connected recovery structure (PCRS). By changing the voltage ratio between the low-voltage and high-voltage sides of the DC/DC converters, the conversion efficiency can be improved, and thus, the braking energy can be effectively recovered. The upper and lower limits of the state of charge (SOC) of the UC are estimated according to the vehicle speed, and associated energy distribution rules are established to achieve a reasonable energy distribution between the battery and the UC. The proposed composite power system and energy distribution strategy were simulated, and a hardware-in-the-loop experiment was carried out on the experimental vehicle. The simulation and experimental results show that under urban driving conditions, the HESS can fully utilize the characteristics of UC, charging and discharging quickly with large current; to meet the instantaneous high power demand of electric vehicles, improve the power performance of electric vehicles, and protect the battery from the impact of large currents. The braking energy recovery efficiency of the vehicle increased by 13.53% in the simulation and by 10.26% in the experimental vehicle test. Highlights • A modified hybrid energy storage system structure for 4WIDEVs is proposed. • A SCRS and PCRS combined connecting model is adopted to improve the energy recovery efficiency. • An improved control strategy based on vehicle speed is employed for energy distribution. • The results show that the proposed structure and control strategy are feasible and effective. • The total energy recovery efficiency increases by 10.26% in the experimental vehicle test. [ABSTRACT FROM AUTHOR]

Abstract Since the beginning of China's reform and opening up in late 1970s, the contradiction between environmental quality and economic development has become increasingly acute. As the main driving force of development, China's fixed asset investment (FAI) has grown rapidly. In the meanwhile, China's energy consumption surged and the environmental pressures mounted. The surge in FAI may have great influences on the environmental quality. On the one hand, the rapid increase in FAI facilitated the development of the secondary industry especially energy- and pollution-intensive industries, which brought about significant amount of energy-related pollution. On the other hand, growing investment on environmental investment is expected to slow environmental deterioration. Moreover, the environmental quality and domestic investment may have potential spatial correlations. In this paper, after fully accounting for the spatial dependence, the relationship between domestic investment and environmental quality in China is quantitatively investigated. Using CO 2 and SO 2 as two representative pollutants, the estimation results indicate that the spatial dependence indeed exists, and total effects of FAI on pollutant emissions are positive. However, there is no evidence that environmental protection investment had expected effects to effectively curb pollutant emissions in China. [ABSTRACT FROM AUTHOR]

Abstract Intelligent Energy Networks are comprised of devices capable of fulfilling their functions in an energy-efficient fashion and with communication and remote control capabilities. Therefore, some of these devices, such as smart energy meters, become attractive for use in the power generation and distribution industry, achieving the vision of Smart Grids. However, many are the challenges that need to be overcome in order to reach a fully-functional and security-aware smart grid. Providing measurement, control, communication, power, display, and synchronization capabilities shall be no easy task for smart meters. In this context, this paper elaborates on a detailed description of the main functionalities that smart meters must provide, along with the analysis of existing solutions that make use of smart meters for smart grids. Moreover, open challenges in the topic are identified and discussed. By the end of this research piece, the reader should be able to have a detailed view of the capabilities already offered by smart meters and the ones they will have available in order to tackle the challenges smart grids present. [ABSTRACT FROM AUTHOR]

Abstract The power industry of China is an energy-intensive one. In recent years, the demand for energy-saving oriented researches has been increased to provide recommendations to the final energy abatement policy making for the industry. Hence, a study which analyzes the typical energy consumption influencing factors and the potential energy-saving capability for the current power industry of China is needed. In this paper, the energy consumption significant influence factors have been picked out and the potential energy-saving capability has been estimated through the analysis conducted under several different scenarios. The results of this work can contribute to the assessment of energy abatement spaces for the power industry of China from now to the year of 2025. At the beginning of the study, 8 factors including social, economic and technical aspects which affect the energy consumption significantly have been selected by Back Propagation Mean Impact Value (BP-MIV) network approach. Then the 8 filtered factors are employed as input in the Back Propagation Adaptive Boosting (Adaboost-BP) neural network model. The Adaboost-BP was trained and tested on existing data set. Being compared with the results on the same data set from grey prediction and regular BP network, the results of Adaboost-BP showed better accuracy over the other two methods. In the final step of this work, the potential energy-saving capability of China's power industry through the year 2025 was predicted using the trained Adaboost-BP network under 3 different scenarios. The results show that the energy consumption estimates can reach at most 319.657 million tons of standard coal under conventional condition at the year of 2025, with 307.8087 and 294.0182 million tons under moderate and advanced conditions respectively. This means that, 11.8483 million tons and 25.6388 million tons of standard coal could be potentially saved at the year of 2025 under moderate scenario and advanced scenario respectively. This work also presented a guideline for energy saving policies making for the power industry of China. [ABSTRACT FROM AUTHOR]

Abstract Nature-based tourism directly and indirectly affects the flora, fauna and environment, thereby reducing the sustainability of tourism destinations. However, the impact of tourism activities on glaciers at glacial tourism sites remains unexplored. Using two typical glacial tourism sites in China as examples, this paper uses the tourism heat footprint (THF) method to examine the impact of large-scale tourism activities on glaciers via local average temperatures. The THF method measures anthropogenic heat release (AHR) from energy consumption and human metabolism per unit area and time divided into seven components of tourism activities: transportation, accommodation, sightseeing, catering, entertainment, shopping and waste disposal. The main results show that the THF values of the Yulong and Hailuogou tourism zones are exhibiting a rapid growth trend, increasing from 8.7 × 10−3 and 4.0 × 10−4 Wm−2 in 1990 to 3.6 and 3.0 × 10−1 Wm−2 in 2017, respectively. These THFs are exerting a significant cumulative effect on the retreat of glaciers by increasing local average temperatures in conjunction with global climate change. These results show that the sustainability of glacial tourism and destinations is threatened by large-scale tourism activities. This study fills a current research gap, enriches the understanding of the impact of tourism activities on glacial resources and expands the analytical perspective of sustainable tourism research. Moreover, this study provides decision support for managing glacial scenic destinations and for the sustainable development of glacial tourism. Highlights • The THF values of the Yulong and Hailuogou increased sharply during 1990–2017. • Tourism activities cumulatively affected glacial retreat via rising temperatures. • The sustainability of glacial tourism and destinations is threatened. • This study enriches existing understanding of tourism's impact on glaciers. [ABSTRACT FROM AUTHOR]

Abstract Regarding to energy efficiency retrofit investment to numerous buildings, which buildings should be invested and which of the retrofit measures should be implemented for investable buildings are challenging tasks. The current literature have studied on choosing energy efficiency retrofit measures in single building, relatively little attention has been paid to the retrofit investment decision-making in multiple buildings. In addition, the existing studies almost put the retrofit cost as an objective that need to be minimized, and the retrofit capital budget is not taken into consideration. This paper proposes a decision-making optimization framework for energy efficiency retrofit investment in numerous buildings under financing budgetary restraint. A multi-objective optimization model with the economic goals being the net present value and time of return, and the environmental goals being the energy saving and emission reduction is presented, and then the intelligent optimization method combing particle swarm optimization and genetic algorithm is designed to search the retrofit investment strategy. The obtained investment strategy could determine which of the buildings should be invested to retrofit, and the combination of retrofitting measures for every investable building. An empirical study is conducted on 27 buildings of non-governmental organization in the state of Delaware in the United States, and the results indicate that the validity of the proposed framework. The findings indicate that the framework is an effective approach to assist the sustainability goal at regional level. Graphical abstract Image 1 Highlights • A decision-making optimization framework for energy efficiency retrofit is proposed. • Retrofit investment in numerous buildings under the capital restraint is studied. • An intelligent optimization method is designed to obtain the investment strategy. • An empirical study is conducted on 27 NGO buildings in the state of Delaware of USA. • The results could well balance economic and environmental goals of sustainability. [ABSTRACT FROM AUTHOR]

Abstract The goal of this paper is to evaluate the advantages achieved through the adoption of low impact energy saving strategies for an independent natural gas fired boiler heating system in a recently built residential building in Rome. For this purpose, an existing apartment was selected as a case study and dynamically simulated in TRNSYS with which the model was validated. Low impact retrofit solutions and heating system management were considered as possible solutions to achieve energy savings. The chosen retrofit solutions consist of envelope elements replacements and building automation controls improvement while heating system management depends on occupants' behavior. Overall, 36 scenarios were considered, starting from the combination of 3 comfort temperature set-points, 2 insulation levels for transparent components, 2 types of zone comfort set-point control with 3 dead-band temperatures. Each case is evaluated in terms of energy results and economic results. The simulation results provide energy savings up to 44% when windows are replaced lowering their transmittance nearby 32%. The choice of a proportional control for zone temperature set-point compared to a simple on-off control guarantee energy saving up to 39% when temperature set-point is low (19 °C) and controls dead-band is 0.5 °C. The effect of different temperature control dead-bands is higher when proportional controls are adopted (up to 40% passing from 2 to 0.5 °C dead-band for 19 °C set-point). Energy consumption reductions up to 63% are achieved if the indoor temperature set-point is lowered 2 °C, underlining the importance of occupants' behavior. At last, an analysis on socio-economic impacts was performed, based on the results of a previous study focused on the externality costs due to pollutants emissions. Highlights • Energy advantages achieved through the adoption of low impact energy saving strategies for an independent gas fired boiler were evaluated. • An existing apartment of a modern residential building in Rome was selected and dynamically simulated in TRNSYS. • 36 energy saving scenarios were considered. • Each case was evaluated in terms of energy and economic results. • An analysis on socio-economic impacts was performed, based on the externality costs due to pollutants emissions. [ABSTRACT FROM AUTHOR]

Abstract Electrical discharge machining is a significant non-traditional technique, widely used in the precise manufacturing field. However, the electrical discharge machining process possesses plenty of energy consumption and hazardous exhaust emissions. Since a sustainable machining technique, external magnetic field assisted, could dramatically develop sustainable machining performance of electrical discharge machining process, this paper presents a comparative study energy efficiency and environmental impact in magnetic field assisted electrical discharge machining and conventional electrical discharge machining. A novel thermo-physical model was proposed to calculate energy distribution under the single/continuous discharge, which was verified by a series of corresponding experiments. Then, based on simulation and experimental methods, a comparative study on the magnetic field assisted electrical discharge machining and conventional electrical discharge machining was conducted to analyze the discharge energy flowing and temperature distribution of workpiece, electrode tool and debris. Moreover, the effects of external magnetic field on the machining performance, environmental impacts and energy efficiency were presented. Eventually, it can be found out that the effect of magnetic field contributes to increasing energy utilization efficiency by 15.2%, material erosion efficiency by 22.6%, and material removal rate by 21.9%. To balance energy efficiency and surface roughness (Ra), the optimal parameter combination is obtained as below: magnetic field intensity: 0.2T, discharge current: 7–9A, and pulse duration: 300s. Highlights • Magnetic field assisted EDM improve energy efficiency and environmental impact. • A thermo-physical model is proposed to calculate energy distribution of MF-EDM process. • Sustainable machining performance of EDM and MF-EDM are comparatively investigated. • The optimal parameter is: magnetic field intensity: 0.2T, current: 7∼9A, and pulse duration: 300μs. [ABSTRACT FROM AUTHOR]

Abstract The Association of South East Asian Nations (ASEAN) is a diverse region characterized by rapid economic growth, demographic change and urbanization. The dominance of energy supply from non-renewable resources in the region means that the increasing energy demand has implications for energy security, as well as adverse local and global environmental effects. Climatic conditions in the region are favorable for renewable energy (RE) resources, especially but not only wind and solar technologies. ASEAN countries differ strongly in terms of their national policy frameworks and progress in renewable energy development; the overall target of 23% renewables by 2025 is very ambitious under current policy frameworks. This paper identifies a gap between these national policies and local governance, especially in urban areas, which requires attention to ensure future target fulfilment. By employing a new combined correlation and decomposition approach at country and city levels, we investigate the determinants of RE expansion and explore the trend drivers in ASEAN countries from 1995 to 2013. An Impact Matrix is developed to position and interpret the relative push (e.g. policy) and pull (e.g. market) impacts on RE development, and to derive policy recommendations for countries and sectors. The results highlight that urban areas should be the focus of RE policy and governance in addition to rural areas. The tremendous impact of economic growth creates a great impetus for renewable energy development, but urbanization is the second pull for renewable energy extensions. Since the two effects are located in the first quadrant of the Impact Matrix, if strategists affect these factors, they will create the most powerful incentive for renewable energy growth. This confirms that if the strategic aim is to promote renewable energy market development, through policy and governance measures, the focus should be on urban areas, non-electricity sectors and the demand side. [ABSTRACT FROM AUTHOR]

Abstract China transport energy consumption grows greatly along with dramatically escalated carbon dioxide emissions. Saving energy in transportation is requested for both reducing energy pressure intensity and decreasing relevant emissions. Large scale energy conservation and emission reduction are Chinese automotive industrys' fundamental objectives. This paper addresses a nonlinear hybrid fuzzy based proportional integral derivative (PID) control methodology to reduce the automobile fuel over-consumption and gases over-emission. After introducing the mathematical model of the automobile Pierburg mechatronic actuator of nonlinear character with parameter uncertainties, its angular displacement is controlled via the proposed PID-fuzzy logic control (FLC) approach. The outputs of the PID controller are the entries of the series-connected FLC. The hybrid topology merges the simplicity and robustness advantages of both the classical PID and the FLC methods respectively. The feedback controller, based on FLC technique, is designed to desirably maintain the angular displacement towards their desired reference values with possible least steady state errors. The proper steady state error elimination will lead to considerable gas emission reduction together with improved energy efficiency. Through Matlab/Simulink tools, the numerical simulations significantly illustrate that the hybrid PID-FLC technique can contribute efficiently in ameliorating the system dynamic behavior in presence of parameter uncertainties. The overall system behavioral analysis enhancement and the proposed controller robustness are experimentally validated. [ABSTRACT FROM AUTHOR]

Abstract Toxic and hazardous sulfur dioxide (SO 2) residue reduction is not only one of the core issues in the preservation process with SO 2 solid antistaling agents in actual table grapes cold chain, but also one of the important ways to improve the cleaner production efficiency of the table grapes. The aim of this paper is to propose an improved preservation process for the table grapes in cold chain by combining the fumigation treatment with the slow-release SO 2 solid antistaling agent. The process was performed to reduce the toxic and hazardous SO 2 residue of the table grapes, improve the cleaner production efficiency of the cold chain, guarantee the quality and safety of the table grapes, and finally enhance the human health. The slow-release SO 2 solid antistaling agent was developed with no pricking holes and relatively stable release rate of the SO 2. According to the comprehensive analysis of the fumigation treatment condition determination, the slow-release SO 2 solid antistaling agent performance, the table grapes quality performance, the SO 2 residue performance and the evaluation on improved preservation process, the proposed improved preservation process with SO 2 residue reduction could effectively reduce the bleaching injury, the decay rate, the threshing rate and the toxic and hazardous SO 2 residue of the table grapes. There was no bleaching injury after the fumigation treatment at the optimal fumigation treatment conditions with 5000 ppm fumigation concentration and 20 min fumigation time. The maximization reduction range of the average decay rate and the average threshing rate of the table grapes was about 91.3% and 44.8%, while the maximization reduction range of the average SO 2 residue in table grapes peels was about 44.7%. The proposed improved preservation process could be extended for other cold chain applications to reduce their SO 2 residue and improve their cleaner production efficiency. Highlights • Proposing an improved preservation process for table grapes cleaner production in cold chain. • Reducing the toxic and hazardous SO 2 residue of table grapes. • Reducing the bleaching injury, decay rate, threshing rate of table grapes. • Improving the efficiency of the cleaner production to guarantee the quality of table grapes. • Enhancing the human health caused by the toxic and hazardous SO 2 residue of table grapes. [ABSTRACT FROM AUTHOR]

Abstract In recent years, although China's energy intensity has gradually decreased, the total consumption of energy commodities has increased sharply. Levying an excise tax on energy commodities is one of the keys to control energy consumption. This paper constructed a Computable General Equilibrium model to simulate levying an energy excise tax in Jiangsu province, which is one of China's strong economic provinces with lower endowments of energy resources. The results show that the energy excise tax is beneficial for energy saving, while levying energy will cause economic and welfare declines. When at a level tax rate of 5%, 10%, and 15%, the loss of GDP will reach 0.27%, 0.66%, and 1.13% respectively, and the incomes of inhabitants and enterprises alike will decrease. When the energy tax revenue used to compensate for the welfare losses suffered by inhabitants or enterprises, there is a double dividend effect (energy saving and increasing income). Moreover, the simulation indicated that a 5% improvement of energy efficiency brings about a "backfire" phenomenon, with an increase of 142% in energy consumption. However, when considering the cost of energy-efficiency improvements, the rebound effect will be significantly decreased. Policy suggestions are further recommended to help improve the energy policy in regard to reducing energy consumption. Highlights • CGE model is proposed to evaluate the effect of energy excise tax. • Levying energy excise tax with refund measures could result in a double dividend. • The rebound effect of energy efficiency improvement is quantified. [ABSTRACT FROM AUTHOR]

Abstract Electric vehicles (EVs) are currently the most promising technology with the potential to transform transportation and energy landscapes to make industry and society more sustainable. Although their adoption has been much faster than anticipated a few years ago, resulting in a significant increase from 400,000 EVs sold in 2013 to more than 3 million in 2017, the coming years will be crucial for determining whether EVs are to become a new transportation industry "standard", the role of which has been held by internal combustion engine (ICE) vehicles over the last hundred years. Not only will innovation in EV batteries determine a "win" or "fail" for EVs, but a significant role in its acceptance will be successful development of a comprehensive EV eco-system, establishing an efficient network of EV chargers as well as attractive and affordable charging tariffs. Furthermore, having insight as to how much money EV users are willing to pay for the charging service (i.e. , willingness to pay) in various circumstances is one of the essential factors in building a successful EV eco-system. That being said, this paper utilizes a gamified survey for exploring a person's willingness to pay for EV charging. The experimental setup includes both the classic (text-only) questionnaire, as well as the game-based questionnaire. Therefore, not only have interesting insights on the willingness to pay for EV charging been identified, but analysis of user experience analysis from the questionnaires suggests that use of gamification is a good approach to performing a survey as it exhibits superior hedonic quality in comparison to classic methods (i.e. , text-only questionnaire). [ABSTRACT FROM AUTHOR]

Abstract There is increasing interest in the idea that energy efficiency has economic, environmental and social impacts beyond energy and cost saving - a 'multiple benefits' perspective. However, present EU-decision making on energy efficiency is based on assessment of a very narrow range of costs and benefits. This paper investigates whether and how advocates of energy efficiency have used multiple benefits to frame their interactions with policy-makers at EU and UK level, and to broaden the appeal of energy efficiency. Nine semi-structured interviews were conducted with key practitioners from industry-backed or trade organisations and environment-focussed NGOs. All respondents regularly made use of multiple benefits arguments. Their experience is that these arguments are most persuasive when linked to the values and priorities of decision-makers and politicians, most of whom do not value energy efficiency as a benefit in itself. Different contexts and different benefits are more or less salient for different stakeholders. This framing sets energy efficiency decisions in a broad economic, environmental and social context. As such it requires more evidence than a simple focus on energy savings, and different sorts of evidence which can connect with a variety of decision makers. The importance of recognising differing contexts, actors, values, priorities has led to the development of an alternative visualisation of multiple benefits, which de-centres energy efficiency. Highlights • 'Multiple benefits' identifies economic, social and environmental impacts of energy efficiency. • Leading NGOs and trade associations use this framing to influence EU policy makers. • Multiple benefits arguments work best linked to values and priorities of policy makers. • Persuasive case studies as well as quantitative evidence are required. • A new visualisation of multiple benefits has been developed, which 'de-centres' energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract Considerable efforts are undertaken to make the transition towards a more Circular Economy (CE). At the same time there is no generally accepted monitoring framework. Rather, what exists is a large variety of measurement approaches that aim to assess the progress. The different assessment methodologies cover different and varied aspects of the CE transition and are seemingly unrelated to each other. Therefore, the main contribution of this paper is the provision of a structured picture of the current stock of CE metrics, including the identification of methodology clusters and the related assessment perspectives. The method of Multiple Correspondence Analysis (MCA) was used to assess 63 CE metrics and 24 features relevant to CE, such as recycling efficiency, longevity and stock availability. The MCA was used to assess how the different CE features are associated to each other and how they are related with each of the 63 metrics. Also, it was determined which combinations of CE features are frequently assessed together. The analysis identified three main clusters of metrics, (1) a resource-efficiency cluster, (2) a materials stocks and flows cluster, (3) a product-centric cluster. The results of the analysis show poor integration of resource-efficiency and product-centric perspectives, while the product-centric and system-dynamic perspectives are least frequently assessed. Further, the analysis provides the most prevailing CE perspectives and it is shown that only a few CE metrics assess CE features that are related to the maintenance of value. The MCA provides a guidance for further metrics development, as it identifies areas with a lower metrics density. For a detailed analysis, a standardized visualisation framework for CE metrics is derived, which allows to compare individual metrics in a simple and illustrative way. The goal of the visualisation framework is to provide guidance for (i) the integration of the most complementary CE metrics and (ii) facilitate further metrics development. Highlights • Structuring of 63 circular economy (CE) metrics along 24 identified CE elements. • Identification of three main clusters of CE metrics and their typical CE elements. • Visualisation framework for a detailed assessment and design of CE metrics. • Identification of most prevailing CE perspectives and their associations. • Guidance for case-specific and complementary selection of CE metrics. [ABSTRACT FROM AUTHOR]

Abstract As a significant basic industry for the national economic development, coal chemical industry is one of the main contributors to energy consumption and CO 2 emission. In this paper, the CO 2 emission in the time series of 2020 and 2030 was calculated and the Logarithmic Mean Divisia Index (LMDI) method was employed to explore the driving forces of CO 2 emission change. According to the industry development, the CO 2 emission in 2020 and 2030 was tentatively predicted. The results show that China's coal chemical industry has experienced a significant increase in CO 2 emission, from 177.87 million ton CO 2 (MtCO 2) to 427.19 MtCO 2 in 2005–2015, with an average annual growth rate of 9.16%. Currently, the coal-to-ammonia industry is the largest contributor. According to the decomposition analysis, the economic growth and energy intensity are the two positive factors and the industry structure is a negative factor to carbon emission change. In 2020, the CO 2 emission will be 617.34 MtCO 2 under slow development scenario and 759.69 MtCO 2 under rapid development scenario. In 2030, the CO 2 emission will reach 1041.90 MtCO 2 and 1440.13 MtCO 2 under slow and fast development scenarios, respectively. The coal-to-olefins industry will take the place of coal-to-ammonia and turn to be the largest one in 2020 and 2030 if no CO 2 capture, utilization and storage (CCUS) technologies are adopted. It is probable that the contribution from coal-to-methanol will also play important role for CO 2 emission due to its rapid development. In addition, by 2030, if coal-to-natural gas industry develops as planned, its CO 2 emission will significantly increase, which has the potential to be equivalent to that of olefins industry. Highlights • The CO 2 emission evolution trend in China's coal chemical industry is analyzed. • The major driving factors of CO 2 emission change are identified and the effect sizes of various factors are evaluated. • The CO 2 emission in 2020 and 2030 is forecasted. • Policy implications to policymakers are provided. [ABSTRACT FROM AUTHOR]

Abstract Cleaner production is the continuous application of an integrated preventive environmental strategy which stressed the importance of environment and human beings. Although the application of cleaner production is becoming more and more mature in different industries, since the complexity of the mining operation itself and its extensive and complex impacts on the ecological environment, the application of cleaner production in the mining industry encounters great challenges. For this purpose, the paper presents some developments and new insights of environmental problems and deep mining strategy for cleaner production in mines. Firstly, the general impacts on the ecological environment of mining industry and the current corresponding solutions as well as future prospects are presented. Secondly, the ecological environment pollution induced by tailings dam and its elimination approaches are reviewed. For the accelerating volume of tailings dam waiting to be processed, the exploration and research of the comprehensive utilization and treatment of tailings is expected to be more effective with larger consumption and wider range of application. The development direction is the establishment of mine without tailings. With the development of modern technology, some intelligent monitoring and warning technologies have helped the mining engineers to keep a vigilant eye on tailings dam continually. Finally, to convert the "harm" of four highs and one disturbance induced by the complex mechanical environment in deep mines into "benefit", various specific measures with relatively high novelty and sustainability are recommended. Moreover, the conception map of safer and more efficient exploitation of resources in deep mines is depicted for industrial best practice and future research directions to enhance cleaner production work in mining. [ABSTRACT FROM AUTHOR]

Abstract Improving thermal insulation of buildings envelopes can reduce their energy consumption and related CO 2 emissions considerably. Searching for new and innovative insulation materials is therefore a key challenge. This paper presents an experimental study to show the effect of adding spent coffee grounds (SCGs) on thermal properties of plaster composite. The obtained results using the box method show a significant decrease of thermal conductivity along with an increase of the coffee ground content, indicating the possible usage of the resulting material as efficient insulation in buildings. It is found that the thermal conductivity of the resulting building material can be decreased from 0.5 to 0.31 W/m.K by adding 6 wt% of CGs to the initial material. To illustrate energetically and environmentally the benefit of using the proposed material, annual simulations were carried out for a typical Moroccan house located in Marrakech. The results indicated that up to 20% of the cooling and heating loads of the building can be reduced if the proposed material substitutes the conventional one. From an environmental point of view, the utilization of the proposed material can reduce up to 1500 kg CO 2 , annually for the studied case. [ABSTRACT FROM AUTHOR]

Abstract Stabilized Emulsions (SE) is a Warm Mix Asphalt (WMA) technique that reduces mixing temperatures to approximately 100 °C, the range of WMA with the greatest reduction in temperature compared to Hot Mix Asphalt (HMA). The term 'stabilized' refers to the good storage stability of the stabilized emulsion compared to that of common emulsions. Another technique that reduces the environmental impact of asphalt mixtures is the addition of reclaimed asphalt pavement (RAP). This paper presents the research results in which the performance of SE-WMA with different amounts of added RAP were evaluated. SE-WMA was produced at 100 °C, and could be prepared with high RAP contents, reducing the consumption of virgin materials and lowering energy needs. The laboratory study and a pavement trial section were used to evaluate the performance of SE-WMA in comparison with HMA. The experimental results indicated that the physical and mechanical properties of SE-WMA, without RAP, are similar to conventional HMA, showing that the effect of reducing mixing temperature does not significantly affect the quality or performance of these asphalt mixtures. The performance of SE-WMA with 25% and 44% RAP, was slightly lower than that obtained from conventional HMA. However, the quality of the SE-WMA complied with the requirements of conventional HMA, indicating that SSE-WMA with up to 44% RAP content is suitable for pavement construction. Deflections measured in the HMA and SE-WMA trial sections without RAP and with 25% RAP showed similar results, although the SE-WMA with 44% RAP showed 8% higher deflection. The energy consumption to produce one ton of asphalt mixture calculated using a thermodynamic model showed that SE-WMA is effective for the reduction of energy consumption in asphalt plants. Overall, the study concludes that SE-WMA with RAP is a sustainable material for pavement construction that could save energy and consume less virgin material than conventional HMA pavements. Highlights • Stabilized Emulsion (SE) is a new Warm Mix Asphalt (WMA) pavement technique. • The performance of SE-WMA without RAP was equivalent to conventional HMA. • The quality of SE-WMA with 44% RAP complied with the requirements of conventional HMA. • A model showed that SE-WMA is effective for the reduction of energy consumption. • SE-WMA with RAP is a sustainable material for pavement construction. [ABSTRACT FROM AUTHOR]

Abstract This paper is a multi-case study of three oil and gas projects in Brazil that investigates the tacit knowledge on how to best manage energy use during the construction phase. Twenty-two in-depth interviews form the primary evidence of the case studies. The methodology incorporates network analysis of concepts that influence energy use to formalize the case studies and collect additional knowledge. The framework comprises thirteen construction activities and twenty-one systems and factors related to design, resources and site characteristics, specific to the construction domain. This set of concepts can influence the energy consumption during the construction phase. Although these concepts are present in nearly every project, their dynamics and their inter-relations with project-specific systems change, depending on the context of the project. The proposed method, which employs network analysis, help identify their interrelationships and relative importance of these concepts. In addition to the opportunities and lessons learned that can guide future energy assessments and improve energy use in construction projects, the results show how promising network analytics is to obtain knowledge usually difficult to perceive in traditional knowledge processes. Besides, this work highlights the importance of supporting collaboration between project team members to study and decide on the plans to manage/reduce energy consumption during the construction phase in oil and gas facilities. While the energy savings are smaller than the upstream and operation phases, it has received much less attention. It is also a phase with much more subjective and contextualized knowledge – making the use of case-based analyses more suitable. Highlights • Supports collaboration in studying and planning energy use during the construction phase of O&G projects. • Three case studies are conducted supported by in-depth interviews. • Network analysis is used to represent construction activities, factors and systems. • The approach represents a meaningful way to formalize the knowledge in the cases. • Can help formalize the knowledge contained in a text case. [ABSTRACT FROM AUTHOR]

Abstract In recent years, urban energy efficiency has received much attention from researchers. However, ignorance of the competitive relationships among regions results in inaccurate energy efficiency. Game cross-efficiency data envelopment analysis (DEA), which can account for the competitive relationships, is a reliable method to measure energy efficiency. First, this paper applies game cross-efficiency DEA to analyze the urban total factor energy efficiency (UTFEE) of 26 Chinese prefectural-level cities from 2005 to 2015 under environmental constraints. Then, a comparative analysis and a concrete analysis are conducted based on the urban energy efficiency. Finally, a Tobit model is used to examine the effects of 10 potential influence factors. The measurement results show that the urban energy efficiency considering the competitive relationship is lower than the traditionally calculated efficiency. Additionally, the urban energy efficiency did not improve during the research period. Furthermore, regression analysis suggests that economic development and city scale can promote urban energy efficiency, while government expenditure, industrial structures, energy prices, foreign investments, research investments and production endowment have negative impacts on urban energy efficiency. According to our results, some implications of theory and practice are discussed for researchers and policy makers. [ABSTRACT FROM AUTHOR]

Abstract Theses on China's low-carbon economy focus on the driving forces of carbon emissions, energy–carbon efficiency, and the carbon–economy nexus. Meanwhile, comprehensive frameworks that assess China's green economy and also analyze its driving forces are lacking. This paper constructs a green productivity index based on the Global Malmquist–Luenberger productivity index to evaluate the development of the low-carbon economy in China. A panel vector auto-regression model is adopted to further analyze the endogenous interactions and dynamic relationships among aspects of the green economy and its influencing factors. Empirical results show that China has seen a balanced development of green economic growth in 2000–2016, achieved in a series of clear stages. To maintain the sustainable growth of the low-carbon economy in the future, China must rely more on technological progress. This research also makes some important discoveries that have not been found in previous studies: the impact of China's industrial structure and energy consumption structure on the green economy are short term, having a duration of impact of approximately four years. Finally, we provide an assessment of provincial green economy development and describe the corresponding policy implications. Graphical abstract Image Highlights • A comprehensive analysis of China's green economy. • A slack-based Global Malmquist–Luenberger index is adopted to calculate the Green Productivity Index in China. • The stage characteristics of green economic development are identified. • A panel vector autoregressive model is used to analyze the interactions among aspects of the environmental economic system. • The findings that the impact duration of energy structure, industry structure, and urbanization on the green economy is about four years. [ABSTRACT FROM AUTHOR]

Abstract Ice cream is consumed daily worldwide and yet its environmental impacts are scarcely known. This paper presents a first comprehensive life cycle assessment of market-leading vanilla and chocolate ice creams, considering both regular and premium products. The results suggest that their impacts are broadly similar across the 18 impact categories considered. For the majority of the impacts, chocolate regular ice cream is a slightly better option than the other varieties. Overall, the regular versions of the product have lower environmental impacts than the premium. Raw materials contribute most to the majority of impacts (>70%). The exception is ozone depletion, which is mainly due to refrigerated storage at the retailer (95%). The impacts are highly sensitive to the duration of storage and the type of refrigerant. Furthermore, the global warming potential of chocolate ice cream is very sensitive to land use change associated with cocoa beans cultivation, increasing the impact by 60%. Considering annual consumption of ice cream in the UK, the total primary energy demand contributes to 3.8% of energy consumption in the whole food sector while greenhouse emissions contribute 1.8%. Future improvements in the supply chain should focus on milk and cocoa production, reduced storage time and types of refrigerant used. Product reformulation to reduce the amount of milk (fat) and sugar should also be considered, in line with the emerging health-driven market trends. In addition to industry and policy makers, the findings of this study will be of interest to consumers, enabling them to make better choices with respect to environmental impacts of most popular ice creams. [ABSTRACT FROM AUTHOR]

Abstract Conventionally, catering waste is stored as per the requirements of Regulation (EU) No. 142/2011 before it is accepted for treatment by waste managers. Due to significant electricity and fuel consumption, the storage and waste management service not only cause substantial impacts on air quality and the climate, but also increase expenditure for catering companies. On-site intensive composting could considerably decrease these negative effects. Moreover, it would contribute to a circular economy by promoting nutrient recycling. In this study, the compost produced by an Oklin GG 10s on-site composter was characterised by high organic matter (>75% of dry matter), total nitrogen (1.85% of dry matter), and total potassium (1.85% of dry matter) contents. The total phosphorus content was relatively low (0.24% of dry matter), with most of it being in water-soluble form (444.60 mg L−1). The compost contained no heavy metals, organic pollutants, and pathogens. The direct impact on air quality was positive (0.042 kg t−1 or 3.4 times lower than that from intensive/centralised food waste composting). This paper presents the results of the compost quality analysis and air emissions evaluation. Highlights • Payback period for the technology in a catering company is about 2 years. • Organic material in the compost is more than 77% of dry matter. • Total nitrogen content was relatively high 1.85% of dry matter. • The total amount of air emissions varied from 0.139 to 0.173 kg t−1 of BDW. • The primary compost was produced within 24 h with no microbiological contamination. [ABSTRACT FROM AUTHOR]

Abstract Various processing parameters in selective laser melting (SLM) affect power profile and scanning time, which directly relates to electrical energy consumption. These processing parameters also control the microstructure of materials, which further influence the mechanical properties of the fabricated parts. In this paper, we investigate the correlation between electrical energy consumption and mechanical properties, and study whether electrical energy can be effectively reduced without significantly compromising mechanical properties by optimizing processing parameters. 316 L stainless steel was used as powder materials. Two key parameters, laser power and exposure time, were selected, and several mechanical properties, including density, hardness, wear resistance, tensile strength, flexural strength, and torsional strength, were tested. The results of electrical energy consumption and mechanical properties were jointly analyzed using growth rate comparison. It was found that the improvement of various mechanical properties with increased electrical energy consumption differs greatly. Density can be effectively increased without significantly increasing the electrical energy, but the electrical energy needs to be greatly increased in order to achieve a high flexural strength. Growth rate three-dimensional maps of mechanical properties and electrical energy consumption are presented as a reference for processing parameter optimization. Highlights • Electrical energy and mechanical properties of SLMed parts were jointly studied. • Growth rate comparison is used to jointly analyze the results. • Acceptable density can be achieved without greatly increasing electrical energy. • Achieving higher mechanical strength requires more electrical energy. • The electrical energy can be effectively consumed for hardness and wear resistance. [ABSTRACT FROM AUTHOR]

Abstract Cities, the core of the global climate change mitigation and strategic low-carbon development, are shelters to more than half of the world population and responsible for three quarters of global energy consumption and greenhouse gas (GHG). This special volume (SV) provides a platform that promotes multi- and inter- disciplinary analyses and discussions on the climate change mitigation for cities. All papers are divided into four themes, including GHG emission inventory and accounting, climate change and urban sectors, climate change and sustainable development, and strategies and mitigation action plans. First, this SV provides methods for constructing emission inventory from both production and consumption perspectives. These methods are useful to improve the comprehensiveness and accuracy of carbon accounting for international cities. Second, the climate change affects urban sectors from various aspects; simultaneously, GHG emissions caused by activities in urban sectors affect the climate system. This SV focuses on mitigation policies and assessment of energy, transport, construction, and service sectors. Third, climate change mitigation of cities is closely connected to urban sustainable development. This SV explores the relationships between climate change mitigation with urbanization, ecosystems, air pollution, and extreme events. Fourth, climate change mitigation policies can be divided into two categories: quantity-based mechanism (e.g., carbon emission trading) and price-based mechanism (e.g., carbon tax). This SV provides experiences of local climate change mitigation all over the world and proposes the city-to-city cooperation on climate change mitigation. [ABSTRACT FROM AUTHOR]

Abstract In the context of China's severe energy and environmental problems, as an alternative vehicle fuel bioethanol is a promising choice because its theoretically renewable and carbon neutral. To guarantee grain security, China is developing non-grain fuel ethanol. Based on a life cycle assessment (LCA), this paper assesses the uncertainty of energy efficiency and environmental performance in the development of cassava ethanol of 1.5-generation bioethanol whose raw materials are non-staple crops. The results show that cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. From an environment perspective, global warming potential and photochemical ozone formation potential of cassava ethanol are better than gasoline, but acidification potential and respiratory inorganics inferior. The Monte Carlo simulation reveals cassava ethanol is feasible compared with gasoline in the case of uncertain variables. Among these uncertain variables, cassava yield, nitrogen fertilizer use, and steam use are the most important variables for energy efficiency and environmental performance of cassava ethanol. Furthermore, this study calculates the potentials for energy savings and emissions reduction with improving key aspects, and gives the suggestions of enhancing the performance of key indicators to promote the development of bioethanol vehicle fuel. Highlights • Cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. • Cassava ethanol decreases GWP and POFP, but increases AP and RI compared with gasoline. • Cassava yield, nitrogen fertilizer usage and steam usage have the greatest impact on cassava ethanol. • The potentials of energy-saving and emission-reduction are calculated with improving key aspects. [ABSTRACT FROM AUTHOR]

Abstract The driving patterns of the electric vehicles describe how users use their vehicles, reflecting the users' habits. These patterns have a positive effect on vehicle energy consumption. In this paper, a two-level clustering model is proposed to determine the driving patterns of electric vehicles. Firstly, the driving pattern characteristics are extracted from the data set of the electric vehicles. Then, the driving patterns including daily driving patterns and multifaceted driving patterns are obtained by a two-level clustering model. The data of 1463 electric vehicles in China were collected from September 1, 2015, to September 1, 2016. Using the proposed model, we obtain five types of daily driving patterns and four types of multifaceted driving patterns. Then, the features of clusters are extracted, and the geographical distribution analysis of the multifaceted driving patterns is conducted. The experimental results reveal that there are many driving patterns of the electric vehicles. Moreover, the effectiveness of the clustering models is verified by the experiments. The customer segmentation based on the driving patterns of electric vehicles is of a great significance for the development of personalized and targeted marketing strategies of vehicle manufacturers and energy efficiency improvement. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the advanced exergy analysis was used to determine the avoidable and unavoidable exergy destructions of the heat exchanger networks (HENs) in a complex natural gas refinery in the South Pars gas field, focusing only on the improvement of the avoidable part. Exergy balances were evaluated for the HENs and the equations of advanced exergy destruction and exergetic efficiency for the HENs were developed. The total exergetic efficiency of the HEN in the plant was determined to be 62.8% that could be increased up to 84.2%, suggesting a high potential for improvement. Also, it was shown that the HEN1 had the most severe condition in the plant with the highest inefficiencies among the other networks. The avoidable and inevitable irreversibilities were calculated for all the heat exchangers running in the plant network. The advanced exergy analysis revealed that the exergy destruction had two major contributors. First, about 59% of the total irreversibility of the system was avoidable and could be eliminated by the well-known optimization techniques. Secondly, only 18 most inefficient heat exchangers (17% in numbers) contributed to more than 61% of the total exergy destruction in the plant network. Hence, there was a high potential for improvement of the operational cost in such a huge consuming energy system. Graphical abstract Image 1 Highlights • The HEN of a complex gas refinery has been analyzed by Advanced Exergy Analysis (AEA). • By AEA, exergy efficiency of the HEN was increased about 34% relative to the old one. • By AEA, the most inefficient heat exchangers in the network were found. • About 61% of total irreversibility of HEN corresponded to only 17% of the heat exchangers. • About 59% of the irreversibility of the HEN was avoidable and can be eliminated. [ABSTRACT FROM AUTHOR]

Abstract Energy conservation and emissions reduction have been the focus of the road transport sector due to its energy-intensive and air pollution-intensive nature. It also embodies the imprints of human technological progress. This paper compares the energy consumption of the road transport sector in China and OECD countries. We used time series and panel data, co-integration analysis, error correction model and dynamic model to study the impacts of the major influencing factors such as income, income structure, urbanization, price, and technological advancement on gasoline and diesel consumption in road transport. Overall, China's fuel consumption is influenced mainly by investment, government expenditure and demographic changes such as urbanization, while the fuel consumption of OECD countries is mainly driven by household final consumption expenditure. In the short run and from a dynamic perspective, China's fuel consumption is less influenced by its historical consumption than current influencing factors, while that of OECD countries is more affected by historical fuel consumption. Based on the analysis and findings of this study, some policy implications are proposed. [ABSTRACT FROM AUTHOR]

Abstract Energy recovery is one of the most important ways to clean production and reduce of carbon dioxide emission. Therefore, in this paper, a trigeneration system (combined cooling, heating and power or CCHP) is suggested to reduce fuel consumption and pollutant emission for building applications. The system consists of two beta-type Stirling engines as prime movers, a heat recovery system, an absorption chiller, and a power generator. The Stirling engine has been modeled based on a non-ideal adiabatic analysis in which the frictional and thermal losses of the engine have been considered using a developed numerical code. For model validation, the specifications of the GPU-3 Stirling engine have been used and the results have been compared with the experimental data and previous models. Moreover, the energy modeling of the absorption chiller has been performed using Stirling engine waste heat. Then, the effects of engine rotational speed, wall temperature of heater, and regenerator length on efficiency, fuel consumption, and carbon dioxide emissions reduction have been studied and the appropriate values have been presented. The results show that in these conditions, the appropriate values for the electrical efficiency and trigeneration efficiency are 27.31% and 74%, respectively. Furthermore, the fuel consumption and carbon dioxide emission of this system have been encountered with reduction of 31.83% and 38.44% in comparison with conventional energy systems for buildings of the same conditions. Highlights • A new arrangement of a trigeneration system driven by Stirling engine for building applications was proposed. • A non-ideal adiabatic model with consideration of the thermal and fractional losses of engine was used. • The appropriate working conditions of the trigeneration system were suggested. • Fuel consumption and carbon dioxide emission were reduced compared to conventional systems. [ABSTRACT FROM AUTHOR]

Abstract Cell variations always undermine the efficiency of energy utilization of battery pack. How does the temperature non-uniformity affect the status of cell variations remains unclear. This paper investigates the underlying mechanisms of the status change of cell variations caused by temperature non-uniformity in a battery pack. First, the status of cell variations has been defined using a graphical model, in which each cell has a coordinate of (capacity, electric quantity). Second, the status transformation caused by temperature non-uniformity has been clarified. Dynamics that describes the thermal-electrochemical effect on the movement of the coordinate for individual cells are firstly established by transformation functions. The movement of the cell locations in the graphical model can vividly interpret the evolution of cell variations caused by temperature non-uniformity with the help of the built transformation functions. Modelling analysis points out that 5 °C increase in the maximum temperature difference among the battery pack can lead to 1.5%–2% capacity loss of the battery pack, therefore the capacity loss caused by cell variations due to temperature non-uniformity should be considered in battery system design. The methodology can be further used to analyze the status change of cell variations in a battery pack caused by all kinds of temperature non-uniformities, benefiting the design of battery management system with high efficiency of energy utilization. Graphical abstract The evolution of cell variations within a lithium-ion battery pack caused by temperature non-uniformity. Image Highlights • The cell variations in battery pack caused by temperature non-uniformity is graphically shown. • The cell variations are defined by a graphical model named the E-Q Diagram. • Thermal-electro coupled dynamic functions are built to interpret the cell variation evolution. • 5 °C increase in temperature difference can lead to 1.5%–2% capacity loss of the battery pack. • The methodology can guide cleaner production of battery system with higher energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract Large amount of energy is consumed to meet user satisfaction in public buildings, which causes carbon emission and results in environmental problem. A direct method to reduce this carbon emission is restricting opening area in public buildings. However, restricting opening area causes occupant satisfaction reduction. Trade-off carbon emission and occupant satisfaction needs to be concerned in building operation strategy design. In this paper, we developed a new integrated modelling method to trade-off between the carbon emission and occupant satisfaction of restriction strategies. We designed a case study in the sixth teaching building (STB) in Tsinghua University. Survey and field investigation were conducted to obtain data and build model. Integrated model result showed that satisfaction increases with the increase of carbon emission, while there exists cluster division and marginal diminishing patterns. By analyzing the performance of strategies with different calculation methods, we found that most optimal strategies open section B and C in STB. Meanwhile, when occupant number is 1,000, 2000 and 4,000, corresponding average satisfaction is 71.4%, 58.8% and 40.4%. It indicates that optimal operation strategy performance changes with the increase of occupant number, but the fluctuation is relatively mild. This integrated model has prospect in guiding energy conservation operation strategy design. It also supports real time monitoring and has potential in interactive platform application. Highlights • We developed a tradeoff model with carbon emission and occupant satisfaction in public building. • Our model found out optimal restriction strategies and strategy performance patterns. • Strategy performance slightly changes with the increase of occupant number. [ABSTRACT FROM AUTHOR]

Abstract Changes in consumer behavior due to a personal carbon trading (PCT) scheme are theoretically attractive, yet untested in practice. In this paper, simulations on the basis of an equilibrium model are used to examine the effects of carbon allowance prices on energy use choice under a particular PCT scheme. It is shown that the equilibrium price of allowances would emerge under the PCT scheme considered here. Further analyses indicate that the quantity of energy consumption under PCT is a nonlinear function of the allowance price, with a sharp kink at the point of equilibrium. When the allowance price is below the equilibrium price, consumers would prefer higher-carbon energy. In contrast, when the allowance price is above the equilibrium price, consumers would choose lower-carbon energy. However, when the allowance price equals the equilibrium value, consumers would purchase lower-carbon energy and higher-carbon energy simultaneously. Furthermore, it is shown that the initial allowance allocation could also affect energy use choice. On the basis of these results, one of the main implications is that the allowance price should exceed the breakeven price to stimulate consumers to switch to green energy and progressively live a low-carbon lifestyle. [ABSTRACT FROM AUTHOR]

Abstract As the world's largest energy consumer, China has set the dual goal of controlling both its total energy consumption and intensity in the 13th Five-Year Plan. As one of the most economically active types of regional units in China, urban agglomerations, composed of adjacent cities with close trade interlinks, play a vital role in energy consumption. Existing studies have provided empirical evidence of industrial transfer as a consequence of urban agglomerations, while a few have focused on whether such industrial transfers could promote the dual goal of controlling both total volume of energy consumption and intensity of all the cities within an urban agglomeration. To bring clarity to this issue, this paper attempts to measure industrial transfer and its impact on total energy consumption and intensity of the Beijing-Tianjin-Hebei urban agglomeration by developing a multi-regional input-output model. The results indicate there is mutual industrial transfer between any two cities within the urban agglomeration. Consequently, total energy consumption has increased by 6258.78 thousand tons of standard coal equivalent while energy intensity has declined by 0.19 tons coal equivalent/thousand Yuan. Finally, a few policy recommendations about dual control of total energy consumption and intensity for urban agglomerations have been proposed. Our study enhances understanding of the critical role of industrial transfer in executing dual control of total energy consumption and energy intensity of urban agglomerations, thus assisting policymakers in finding ways to achieve sustainable urban transitions. Highlights • Industrial transfer between cities within an urban agglomeration is defined. • Industrial transfer calculation method based on input output analysis is proposed. • Impacts of industrial transfer on energy consumption and intensity are measured. • Policies for dual control of total energy consumption and intensity are suggested. [ABSTRACT FROM AUTHOR]

Abstract The sustainability of the water-energy-food (WEF) nexus is a significant challenge faced by developing countries, especially China. Evaluating the sustainability status of China's water-energy-food, and improving its sustainable use, may provide good physical conditions to support China's future development. This paper applied the Pressure, State, and Response (PSR) model to select evaluation indexes. A combination weighting method was used to combine two objective weighting methods to determine index weights. The study constructed the classical field, the limited field, and the matter-element to be evaluated. This allowed the establishment of an improved matter-element extension model to evaluate the sustainability of the water-energy-food nexus; the model was then used to quantitatively evaluate the sustainability of China's water-energy-food nexus. The simulation results indicated that in 2005, the sustainability of China's water-energy-food was at a relatively low efficiency rank. By 2015, the sustainability of China's water-energy-food had reached a general efficiency rank. The results suggested that the sustainability of China's water-energy-food system significantly improved between 2005 and 2015; however, the improved sustainability remained at a general status (The general status means that the sustainability of water-energy-food nexus in China can meet the basic development needs, but it is far from the optimal state and needs further adjustment and improvement). Thus, China should improve its current utilization patterns for the three resources and consider them as a whole. This would help realize synergistic resource use and enhance their sustainability. Highlights • The sustainability of WEF nexus is a severe challenge faced by developing country. • An improved matter-element extension model to evaluate sustainability of WEF nexus. • The sustainability of China's WEF system significantly improved from 2005 to 2015. • China should improve its utilization patterns for the WEF and consider it as whole. [ABSTRACT FROM AUTHOR]

Abstract The construction industry is one of the largest energy consumers and CO 2 emitters in China. This paper primarily aimed to explore the driving forces of energy-related CO 2 emissions (ECE) from the construction industry. Adopting a comprehensive decomposition approach, this study decomposes the changes in ECE into eight factors. The main results provide the following findings. (1) Industrial activity was the largest factor pushing the growth of CO 2 emissions, driving up CO 2 emissions in all years and contributing to a 174.65 Mt CO 2 emissions increase in total. (2) In contrast, advances in industrial output technology represented the dominant factor inhibiting CO 2 emissions, cumulatively reducing CO 2 emissions by 99 Mt. (3) The effects of potential energy intensity changes and industrial output technical efficiency fluctuated in different years but exerted positive effects on CO 2 emissions over the entire period. (4) Additionally, changes in spatial structure, energy-saving technology, and energy consumption structure as well as energy usage efficiency all contributed to emissions reductions to varying degrees. The CO 2 emissions of the construction industry increased in all provinces, while emissions changes and their factor effects varied distinctly across provinces. Highlights • Direct and indirect CO 2 emissions in China's construction industry are calculated. • Impacts of driving factors are quantified by combining the PDA and IDA methods. • Industrial activity is mainly responsible for CO 2 emissions increase. • Industrial output technology change is the dominant curbing factor. • Factor effects of China's construction industry vary distinctly across provinces. [ABSTRACT FROM AUTHOR]

Abstract This paper is the first to introduce the concept of Smart Energy-Efficient Production-Planning (SEEPP) for a general Job-Shop manufacturing system in the presence of Grid-connected Microgrid with wind power generation. To cope with the unpredictability of wind speed and the uncertainties of demands, a novel risk-based Robust Mixed Integer Linear Programming (RMILP) model is mathematically formulated. The last aim of the model is to minimize the total day-ahead cost of the system considering peak demand charge. The results show the capability of the proposed integrated framework to obtain a constructive trade-off between scenario-based cost deviations, and heat and power imbalances considering the attitude of Decision Makers (DMs) toward risk. The results further indicate that the proposed SEEPP concept is able to produce products with at least 1.95% less cost than conventional manufacturing systems, although it supports a much wider range of demands for products. The performance of the model is analyzed and evaluated in terms of accuracy, robustness, and computational efficiency. [ABSTRACT FROM AUTHOR]

Abstract Application of consequential lifecycle assessment modelling has gained increased interest in the area of solid waste management. In such assessments, identification of affected technologies and choices of system boundary setting are of key importance. With the aim of investigating how previous consequential lifecycle assessments of solid waste management systems have tackled these issues, a review was performed of 36 previously published studies. The intention is to contribute to improved understanding of the challenges of performing consequential lifecycle inventory modelling of solid waste management systems, which could facilitate future studies. Results demonstrate a strong relation between the selection of affected energy production technology and overall GHG-emissions. In general, assuming that energy provision from less polluting technologies is affected by studied changes will commonly discredit waste-to-energy technologies and promote material recycling. However, made choices were also in many cases not justified. Materials substituted by waste derived goods are frequently represented by average data. The detected inconsistency in how energy provision and material provision are modelled could result in biased results, and care should be taken to minimize this risk. Four aspects are identified where current practice in system boundary setting choices is diverse and where those choices could have significant influence on overall results; counterfactual waste management, fate of materials avoided through material recycling, cascading effects and rebound effects. This paper argues that there is a need for increased transparency and coherence in identification of affected processes/technologies, as well as for a broader approach in system boundary setting, if studies have the aim of serving as relevant input for decision makers. [ABSTRACT FROM AUTHOR]

Abstract This research experiment is the first study to provide detailed insights into resource use by guests staying in self-contained B&B style accommodation. Self-contained accommodation is a neglected yet important sub-industry in the hospitality sector, as it represents the largest and fastest growing share of accommodation providers in many regions. The study provides valuable data from a smart metering system, collecting data every minute over four seasons and indicates sustainable consumption opportunities using renewable energy, guest behaviour change and eco-conservation. Our results reveal that guests, when exposed to sustainability advice and communication (i.e. Intervention Group), saved 27% electricity, 22% gas, 22% water and 10% firewood. Differences between Intervention and Control Groups were also observed in terms of daily peak consumption and seasonal patterns. There are further saving opportunities, but findings also highlight social practice complexities to navigate guests' individual thermal comfort knowledge and daily routines. Transitions can be achieved through advanced smart services for direct and indirect customer feedback and host training. This paper is the first to detail findings from smart meter monitoring using high resolution at tourist accommodation, providing new insights into social practices and analysis of water energy nexus. [ABSTRACT FROM AUTHOR]

Abstract City has always been a concentrated area of consumption and pollution in a country or region. Solutions to the dematerialization of city would exert a profound impact on the entire socio-economic system. And the issue of resources and environment in Beijing, the center of China’s politics, economy, and culture, becomes a focus of attention both domestically and internationally. In this paper, we used the economy-wide material flow analysis to describe the socio-economic development and the current situation of resources and environment in Beijing during the period 1992–2015. Based on this, Tapio decoupling model and the logarithmic mean divisia index method were used to analyze the level and influencing factors of dematerialization in Beijing. The results of the study showed that: From 1992 to 2015, GDP of Beijing increased from 61.25 billion yuan to 623.45 billion yuan, at the same time, direct material input and domestic processed output also increased from 139.88 million tons and 78.63 million tons in 1992 to 205.17 million tons and 166.27 million tons in 2015 respectively. Judging from the change of the decoupling relationship between economic growth and resources and environment, the level of dematerialization in Beijing was continuously increasing. And the dematerialization level of resource consumption was slightly better than that of pollution discharge. The high expansion of population and economy was not conducive to the realization of dematerialization in Beijing. However, the decrease of the intensity of material utilization played a crucial role in the process of dematerialization in Beijing. Moreover, increases in material circulation and social overall level of cleaner production were beneficial to the realization of dematerialization. [ABSTRACT FROM AUTHOR]

In the current paper, a suggested process of coupled ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) to produce isotonic solution (IS) and drinking water from coastal well water was investigated. Due to its high fouling potential, the feed water was pretreated using UF. Results showed that UF eliminates almost the totality of natural organic matter (NOM), and a relatively high portion of calcium (calcium rejection ∼75%) due to the complex Ca-NOM formed. To understand the fouling mechanism, previously developed mathematical models and equations were adopted. It was shown that the fouling mechanism for UF fits the blocking pores model. For NF, the extended model using cross-flow mode showed a slight difference compared to UF (No compression cake phase). It was concluded that, with some experimental precautions, fouling mechanism of the NF membrane used is internal pore blocking mechanism. Due to its attractive quality, the brine of NF was used to produce drinking water by RO treatment. The energy consumption of the UF-NF-RO system was investigated for different operating conditions. Finally, the permeate of the UF-NF process was compared to a commercialized IS. It was found that the two solutions revealed a remarkable similarity. However, a specific post-treatment should be added to the process to accomplish the pharmaceutical exigencies of IS. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of urbanization on provincial energy efficiency in China. Using panel data of 30 Chinese provinces between 2003 and 2014, we adopt a stochastic frontier model to estimate energy efficiency in China, and apply a series of spatial panel data models to tackle spatial dependence of energy efficiency between provinces. Our results show that the overall impact of urbanization on energy efficiency is negative in China. These results are established after controlling for spatial correlation and other confounding factors, and are also robust to various model specifications. We also document that the impact of urbanization on provincial energy efficiency manifests through both a direct negative impact induced by the focal province's urbanization process, and an indirect positive spillover effect caused by urbanization in adjacent areas. [ABSTRACT FROM AUTHOR]

Machining workshop is a widely distributed manufacturing system that consumes massive energy in a low efficiency. In recent years, the increasing pressure from energy price and environmental directive have forced machinery manufacturers to address energy efficiency monitoring and management to improve economic benefits and environmental performance. However, due to the complicated energy flow and dynamic energy changes of the machining workshop, machinery manufacturers still lack an effective method to monitor and manage the energy efficiency in a practical manner. To this end, this paper proposes an energy efficiency monitoring and management system with the support of the newly emerging Internet of Things (IoT) technology. Firstly, the energy characteristics and energy efficiency indicators of the machining workshop are analyzed and defined. Then the framework of the IoT based energy efficiency monitoring and management system is proposed. The key approaches for energy efficiency monitoring and management are then illustrated. Finally, an industrial application is demonstrated to validate the effectiveness and benefits of the proposed system. With the application of the proposed system, potential opportunities for energy consumption decrement and energy efficiency improvement can be identified. Machinery manufacturers can easily reduce energy consumption and energy cost by managing the machining process. [ABSTRACT FROM AUTHOR]

Despite the positive momentum achieved by the renewable energy sector in recent years, there are substantial challenges that need the attention of the global community, and one of the more pressing issues is dealing with the deleterious external costs of power generation. One of the parameters to compare costs of energy across various technologies is levelised cost of energy (LCOE), but it has been conventional practice to neglect the external costs in estimating the LCOE of power generation technologies. Furthermore, as LCOE is a critical indicator for policy and decision makers, there is a need to juxtapose actual costs of renewable and conventional power generation technologies. This research paper attempts to internalise some of these external and GHG emission costs across various power generation and storage technologies in all the G20 countries, as they account for 85% of global power consumption. As future investment decisions are largely influenced by costs, estimates in this research prove renewables and storage to be far cheaper than fossil and nuclear sources by 2030, even without considering external costs. The myth that renewables are ‘way too expensive’ has been debunked repeatedly, and the cost decline of wind and solar photovoltaic (PV) technologies have outpaced most industry expectations. The results of this research not only substantiate this trend, but also statistically display that all the G20 countries have the opportunity to decrease their energy costs significantly, between now and 2030. Renewable energy technologies offer the lowest LCOE ranges across G20 countries in 2030. Utility-scale solar PV generally shows the lowest values ranging from 16 to 117 €/MWh el and onshore wind LCOE range is from 16 to 90 €/MWh el . Rooftop solar PV generally offers the next lowest LCOE ranging from 31 to 126 €/MWh el , followed by LCOE of offshore wind power ranging from 64 to 135 €/MWh el . Solar PV and battery systems are highly competitive on an LCOE basis at utility-scale ranging from 21 to 165 €/MWh el and at residential scale from 40 to 204 €/MWh el . The G20, as well as other countries, can continue to develop their economies in a sustainable manner, along with substantial co-benefits in adjacent policy fields such as higher national welfare, better health of citizens, lower respective health costs and improved energy security. [ABSTRACT FROM AUTHOR]