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Abstract Heat pipe is being widely used nowadays in industry as a high efficiency heat transfer device. For the development of heat pipe, many attempts have been made to enhance its performance by mimicking biology, including the optimization of structure and flow patterns in heat pipe wicks. Constructing biporous, composite, and nanopillar wicks with aim of achieving hierarchical structure has been found through the learning of natural solutions. And bionic approach studying plant water migration provides another path to the fluid flow enhancement inside heat pipe as well. Forces involved in the water migration process in plants include the capillary effect, friction, gravity and transpiration effect, and all these happen in heat pipe as well. The investigation through plant water migration can provide a guidance to the heat transfer performance analysis and wick structure design. Magnetic Resonance Imaging (MRI) technology is used in this paper to scan live plants, providing the possibility of visualizing the internal structures in vivo and obtaining water transport velocity in xylem vessels. In addition, a novel mathematical model on the forces in plant water migration and heat pipe is proposed in this paper. The result from mathematical calculation is compared with the experimental measured result. This paper also successfully put transpiration effect and friction into consideration, as our innovation syntheses of a low level of hierarchical structure and integrates integral wicks includes evaporator, adiabatic, and condenser as well. [ABSTRACT FROM AUTHOR]

Abstract This paper aims to evaluate severe accident in VVER-1200. The consequences of severe accident depend greatly on containment safety features and its performance in retaining radioactive material. The specific type of LOCA includes hot leg or cold leg break in the primary coolant circuit. For both simulations a loss of offsite power is also initiated after 500 seconds. It shows that the Reactor Cooling System (RCS) pressure drops from 155 bars to below 5 bars in both the cases to reduce RCS leakage. Reactor Core Thermal Power, Nuclear Flux Power and Turbine Load fall significantly after 23.5 seconds because of the occurrence of Reactor Trip. Both HA-1 and HPI are activated to prevent Core damage. The flow of HPI drops to zero after the loss of offsite power. The temperature of the fuel falls below 200 ºC within 150-200 seconds of the malfunction in both the cases. The corresponding pressure, temperature, void fraction of reactor etc. are analysed in this paper. The results obtained satisfactorily meet all PSAR (Preliminary Safety Assessment Report) data regarding Loss of Coolant Accident (LOCA). The results provide useful information about safety features of VVER-1200 in case of Loss of Coolant Accident (LOCA) concurrent with loss of offsite power. [ABSTRACT FROM AUTHOR]

Abstract Over the past 40 years, energy consumption has increased dramatically to become a significant crisis faced today. The peak demand is growing at approximately 50% greater than the demand base growth in many Australian cities, which, in turn, requires greater finite resources and infrastructure to meet the required generation capacity needed. Currently, approximately 40% of electrical energy is consumed by HVAC systems in commercial building. This level of energy consumption emphasizes the necessity of developing an eco-friendly air-conditioning system, where possible, harnessing low-grade thermal energy such as solar energy rather than electricity. In this paper, a comparison of energy performances of three different HVAC is undertaken. Mathematical models are developed with TRNSYS17 to simulate the HVAC system within a typical small commercial building with various cooling options. The model is implemented to provide a comparative analysis across various cooling systems such as Vapour Compression System, Vapour Absorption System and Desiccant Evaporative Cooling System. This paper implements the developed model to investigate and compare the energy consumption and running costs over an eight-month cooling period of the widely used Vapour Compression System against alternative solar assisted cooling options for a sub-tropical location of Brisbane, Australia. [ABSTRACT FROM AUTHOR]

Abstract This paper examines the how the South Asian countries are addressing their energy deficiency as the capacity to refine imported crude oil is limited except India. India has developed substantial refining capacity (247.6 million tons per annum) compared to Pakistan (18.8 mtpa) and Bangladesh (1.5 mtpa). India's refining capacity is being currently utilized nearly 100%. Having no local refining capacity, Nepal and Bhutan import refined petroleum products entirely mainly from India. The demand for refined petroleum products in Bangladesh outstripped the quantity produced by the country's single aged oil refinery over 3 times. Similar problem is faced by Pakistan. This paper provides an analytical framework based on the data collected from the region and argues that a regional energy trade will create a mutually beneficial platform for effective utilisation of natural resources which will increase reliability of power supply, build economies of scale, enable mutual support during contingencies, transform sectors on a large scale and contribute to economic growth. This trading platform will promote market integration in energy (oil, gas coal) and energy-related goods and services. [ABSTRACT FROM AUTHOR]

Abstract The global consumption of natural gas is expected to increase at an average of 1.6% over the next 5 years from 3.7 trillion cubic meter (tcm) used in 2017. Although the current use of gas in power generation is dominant followed by industry, residential and other sectors during 2011-2017, the global industry is expected to be the main driver for gas consumption followed by power generation, residential and commercial and other sectors by 2023. Many countries including Bangladesh use natural gas primarily for power generation. Among the main reason was energy security, availability of smooth supply of own relatively cheaper natural gas. As the demand for power has increased and the country could not extract indigenous discovered coal due to complex mine water management and agricultural land rehabilitation, its indigenous fuel supply restricted utilizing installed capacity of power generation, impeding industrial growth and development. This paper reviews the status of natural gas in Bangladesh and the engagements of local and international oil companies in natural gas exploration. The paper highlights the need for transboundary gas importation and associated infrastructure to support its development activities. It is recommended that the indigenous and transboundary gas to be managed efficiently and a long-term strategy for sustained supply of fuel from multiple sources to be formulated to maximise the energy security and achieving Bangladesh Vision 2041. [ABSTRACT FROM AUTHOR]

Abstract China is confronting with large amount of renewable energy curtailment, while the distributed renewable generation is in an explosive growth. To enhance the renewable energy utilization, China has embarked on reforms on distributed generation PV (DG PV) trading in the distributed energy market. This paper introduces the new reform that put forward three DG PV trading patterns –direct trading between DG PV and consumers, commissioned power grid sales and full generation purchased by the grid. We analyze the impact of DG PV trading reform on interests of stakeholders in the DG energy market. We argue that increasing integration of uncertain DG and efficient operation of DG energy market require higher technologies in storage, forecasting, smart monitoring for the grid to guarantee system reliability and security. Future roles of DG energy market are sketched out to integrate the market participants in a user-friendly and comprehensive way. This paper will be insightful to provide a framework for future Chinese DG energy market development and help it transit to an open retail electricity market in the future. [ABSTRACT FROM AUTHOR]

Abstract Despite a significant progress in electrification over the last decade, more than 1 billion people have no access to electricity, and about 3 billion use solid fuel or kerosene for cooking and heating purposes. More than 95 % of them live in sub-Saharan Africa or developing Asia, and around 80 % are situated in rural areas. Conventional approach to power supply such as transmission grid extension is not economical due to high investment and connection costs. Technological progress has shifted down capital costs of renewable off-grid solutions. However, in the most cases, it is not enough to reach feasibility of these solutions due to weak investment conditions and weak purchasing power of the local population in these areas. The choice of business model can have a vital role in bringing electrification and connectivity to rural areas, providing flexibility and adaptability of the technology to the market conditions. Analysis of existing literature on business models for off-grid solutions concludes that the model for rural areas in developing countries should be more service oriented, be scalable to various use case scenarios, should provide good risk balance between customer and provider, and should enable transparency and quality of service. This paper analyses recent developments in off-grid system solutions for sub-Saharan Africa and provides classification of business model innovations. Based on the analysis, the paper proposes an innovative business model for Fusion Grid project, scalable mini-grid integrated with connectivity solution. Feasibility of the project is tested for three different cases, depending on the type of the rural community. Results suggests that combining micro-grid based power supply and internet connection as one service can contribute to a viability of the project, and, furthermore, can contribute to achieving global electrification goal. [ABSTRACT FROM AUTHOR]

Abstract Uncertainties of cooling load may make cooling system oversized. Most of previous studies implement probabilistic-based uncertainty analysis, intending to achieve optimization and reliability simultaneously. However, how to reduce the load uncertainty has received little attention. This paper investigates the impact of water storage on the design of cooling system considering load uncertainty. Information entropy is used as a convergence index of load uncertainty and used to determine how many random simulations should to be performed. A cooling system configured with water storage (system B) and another system without water storage (system A as a comparation system) are investigated in this paper. In this paper, the configure of system A and system B are optimized respectively. The result shows that the capacity distribution of system A is consistent with the distribution of extreme loads. But, the capacity distribution of system B is more concentrated as the water storage can reshape the load curve. Water storage improves the flexibility of system B. Therefore, system B is more reliable and economical than system A. [ABSTRACT FROM AUTHOR]

Abstract The local wind environment and daylight conditions of buildings directly affect the safety and comfort (e.g. thermal environment and lighting environment) of the residents and staff, and influence the energy consumption and energy efficiency of building's operation. However, in the view of a planning designer, it is likely to pay more attention to the building's functional arrangement, appearance and space utilization, but the problems of area ventilation and daylight condition may be neglected. This paper takes a layout design of a commercial building group in Haidong, Qinghai Province as an example to demonstrate, for an urban planner, how to use the CFD and building lighting simulation technology to carry out the preliminary evaluation on an initial design scheme. Simulation results indicated under local meteorological conditions, the initial design scheme fully considered the cold air infiltration in winter and natural ventilation in summer, as well as safety issues in the human walking area, which formed a good local wind environment. However, the problem of poor daylight condition in some areas requires adjustments and modifications based on actual circumstance. From the examples presented in this paper, the numerical simulation techniques play an important role at the initial stages of planning and design to detect the design defects timely and provides a basis for subsequent adjustments later. Meanwhile, this paper also provides a reference for interdisciplinary cooperation between urban planners and HVAC engineers. [ABSTRACT FROM AUTHOR]

Abstract Battery is the bottleneck technology of electric vehicles. The complex chemical reactions inside the battery are difficult to monitor directly. The establishment of a precise mathematical model for the battery is of great significance in ensuring the secure and stable operation of the battery management system. First of all, a data cleaning method based on machine learning is put forward, which is applicable to the characteristics of big data from batteries in electric vehicles. Secondly, this paper establishes a lithium-ion battery model based on deep learning algorithm and the error of model based on different algorithms is compared. The data of electric buses are used for validating the effectiveness of the model. The result shows that the data cleaning method achieves good results, in the case of the terminal voltage missing, the mean absolute percentage error of filling is within 4%, and the battery modeling method in this paper is able to simulate the battery characteristics accurately, and the mean absolute percentage error of the terminal voltage estimation is within 2.5%. [ABSTRACT FROM AUTHOR]

Abstract Following time-constraining obligations under 2015 Paris Agreement, nations are racing to integrate more renewable energy generation into their power systems than ever before. While solutions for mitigation of renewable energy negative effects to power system stability exist, they are still complex and expensive. One of the most promising technologies, battery energy storage, is widely advocated, but is still unable to solve basic challenge of renewable energy integration – low inertia and provision of sufficient fault currents. This paper presents a practical enabling technology in a form of synergy between a battery energy system and a synchronous machine, which can support fully renewable power system while providing nominal power system inertia. For simplicity, the case for this technology is presented on an example of an Isolated Power System capable of 100% instantaneous renewable operation for prolonged periods of time. High-speed measurements during both steady-state operation and performance under fault conditions were recorded and presented in the paper. [ABSTRACT FROM AUTHOR]

Abstract Moving away from a centralized diesel generation plant, future isolated power systems will increasingly depend on renewable generation which can be distributed across larger areas, due to lower energy density of renewable resources. In future distributed generation systems, a key enabling technology for operating high renewable energy penetration system will be a high-speed communications infrastructure. This new infrastructure can then be used for real-time power system monitoring and control of customers loads, as well as for control of the distributed generation. Our paper presents the concept of a high-speed wireless network capable of real-time monitoring and control of both loads and distributed generation across an isolated power system. The paper also presented real-world measurements taken during a multi-year operation of an isolated power system, and specifically, presented how utilizing communications networks can prove beneficial to increasing renewable penetration in the system whilst preserving power system stability. [ABSTRACT FROM AUTHOR]

Abstract The use of electric energy substitution technology on the demand side provides a low-carbon solution for energy supply, which is more efficient and environmentally friendly. In order to analyze the economic impact of the indoor temperature set-point on the air-source heat pump heating system considering the thermal comfort, this paper proposed an optimal dispatching method that aims at the lowest daily operating cost. Firstly, a model combined an air-source heat pump heating system and a building was established. Secondly, an optimized dispatching model with the lowest daily operating cost as the goal was built. Finally, a typical case was built and study. And based on weather information released by the Meteorological Station, the system was optimally scheduled at the hour level on a typical day in winter by changing the indoor temperature set-point. Numerical studies demonstrate that the use of the optimized scheduling method proposed in this paper can significantly reduce the electric bill of the air-source heat pump heating system. It will provide customers with a guideline to save electric bill. [ABSTRACT FROM AUTHOR]

Abstract The results of an optimized design of grid-connected renewable energy system for University building are presented in this paper. Integrated modelling, simulation, optimization and control strategies are used to test the performance and select the best hybrid renewable power system. The main objective is to design a grid connected renewable energy system to meet the electric load of the building with high penetration of renewable energy, low greenhouse gas emissions, and low cost of energy. Hourly simulations, modelling and optimization were performed to determine the performance and cost of the hybrid power system configurations using load following and cycle charging control strategies. The results show that the grid-tied solar PV/fuel cell hybrid power system offers a good performance for the tested system architectures. With a solar PV capacity of 500 kW and fuel cell capacity of 100 kW integrated with the grid, the total energy generated from grid-tied renewable energy system to meet the desired load is 26% from the grid (purchase), 42% produced from the solar PV, and 32% from the fuel cell. From the total annual power produced, 95% is used to meet the AC primary load of the building and 5% is the sellback to the grid. The daily performance and electricity generation from the proposed grid-tied solar PV/Fuel cell power system is also presented in this paper. The proposed grid-tied solar PV/fuel Cell hybrid power system with the sale of electricity back to the grid has a high renewable fraction (40.4 %), low levelized cost of energy (71 $/MWh), and low carbon dioxide emissions (133 kg CO 2 /MWh). [ABSTRACT FROM AUTHOR]

Abstract Energy saving is actually recognized as one of the most significant ways to reduce primary energy consumption and pollutant emissions. Due to the remarkable importance of heating systems and heat distribution grids, Siram by Veolia and the University of Parma have developed an optimal control system for District Heating Networks. Usually building control systems are designed to manage plants relying on past experience: the optimal control system described in the paper defines plant management strategy on the basis of the future behavior of the systems and the external environment. The proposed control system has been applied to the heating system and the distribution network of a school complex in Podenzano (Emilia-Romagna region). The district heating supplies heat to three different buildings (primary school, secondary school and sports hall). The heating plant is composed of three generators (two fed by natural gas and one by wooden biomass), a Thermal Energy Storage, two main distribution manifolds (supply and return) and three secondary circuits, which distribute heat to the buildings. In the first part of the paper the control algorithm is described, split into plant simulation models and the optimization algorithm. In the second part, the real application and the new communication architecture applied on site are outlined and, finally, the obtained results are reported highlighting the management strategies of generators and pumps. The optimal control strategy application gave important results in terms of energy saving, in particular the energy supplied to the buildings dropped significantly, this is the result of knowing the building behavior in advance. [ABSTRACT FROM AUTHOR]

Abstract This paper describes a preliminary analysis on the integration of renewable energy systems in smart microgrids. The initial theoretical evaluations are referred to the case study of a laboratory DC microgrid interconnecting: electric mobility, stationary storage systems and renewable energy sources in a smart grid scenario. Specific power architectures for the integration of a 7kWp solar generation system with the considered microgrid are analysed and compared, in terms of efficiency and costs, in order to support the choice and the design of optimal solutions. Modeling and simulations of the related components are carried out in Matlab-Simulink environment in order to evaluate the performance of different embedded maximum power point tracking techniques, working in balanced and unbalanced irradiance conditions for the considered PV generation system. The promising results and the considerations reported in this paper highlight the importance of using the proposed smart power architectures and the related control techniques to support the optimal use of sustainable energy generation systems. [ABSTRACT FROM AUTHOR]

Abstract Economic structure and industrial structure play an important role in attracting the type of FDI. By studying the FDI impact on ecological environment in Shandong province, this paper explored its influence on energy consumption from three aspects: scale effect, structure effect and technology effect. Based on the time series data of Shandong Province from 2000 to 2016, the mechanism of FDI on energy consumption in Shandong Province was studied from three aspects: scale effect, structure effect and technology effect, By combining regression model and simultaneous equations model, the paper studied the magnitude and direction of various effects of FDI on energy consumption in Shandong Province from both qualitative and quantitative analysis. The results showed that FDI had negative scale effect, structural effect and positive technical effect on energy consumption in Shandong province, the total effect was negative. Based on this, the paper put forward the optimization strategy from the perspective of the transformation of new and old kinetic energy in Shandong Province.It provided policy suggestions for the government to implement the transformation of new and old kinetic energy, so as to promote the economic development, industrial structure transformation、upgrading and the transformation of new and old kinetic energy in Shandong Province. [ABSTRACT FROM AUTHOR]

Abstract The main objective of this paper is to present a new and cost-effective Information and Communication Technology (ICT) tool that can lead to efficient energy management in buildings and optimal operation of electricity networks with increased share of Renewable Energy Sources (RES) and Electric Vehicles (EVs). The new ICT infrastructure is based on the Digital Audio Broadcasting (DAB) standard and its interoperability with smart metering technology, Intelligent Transportation Systems (ITS) and Building Automation Systems (BAS). The main idea involves the attachment of a DAB receiver to electric devices (from small household appliances up to EVs and solar systems and other RES). In this paper, the DAB protocol is described, enabling high cyber-physical security. Moreover, the results of addressing a thermostatically-controlled load using DAB-signaling in Switzerland are also presented. The next steps envisioned are i) the validation of the final protocol version and of the DAB receivers for various electric appliances and DR schemes and, ii) demonstration of the new technology in real-life cases through the National DAB broadcaster in Greece. [ABSTRACT FROM AUTHOR]

Abstract The growing interest in green building is driving the development of energy efficiency building models. One of the essential elements is an effective and efficient Energy Management system. Traditionally, the system contains lots of meters measuring each appliance. Non-Intrusive Load Monitoring (NILM) is a technique for estimating power consumption of each appliance by disaggregating the end-use power consumption measured by a single meter. However, existing NILM are facing two main problems: 1) some of the small appliances and the similar appliances cannot have their power consumption estimated, and 2) NILM requires a long learning process, which means that a new learning process might be needed if a new appliance is connected. To tackle these problems, this paper proposes to use Intrusive Signature (IS) and Power Line Communication (PLC) for circuit-level load decomposition. The paper focuses on the development of a device using frequency domain signature as the IS. The prototype is developed and deployed on the circuit. The results show an accuracy between 83% to 93%. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the Yangtze River Delta city group for the study, first, using data envelopment analysis estimates the energy efficiency of the city, and found that the Yangtze River Delta city group showing lower energy efficiency overall. Within the urban agglomeration 26 prefecture-level cities, Zhoushan is the only one achieving relatively effective energy efficiency. The spatial heterogeneity of energy efficiency in the urban agglomeration in the Yangtze River Delta is then measured using the Moran's I index (including local), confirming the existence of low-energy efficiency clusters centered around Hefei and clusters of high-energy agglomeration centers centered around Hangzhou. Then the spatial error model is used to test the various factors that affect the energy efficiency of the urban agglomeration in the Yangtze River Delta based on the circumvention of spatial heterogeneity. The conclusion shows that there is a positive correlation between industrial structure, investment, scale, foreign trade and energy efficiency. Government influence and system is negatively related to energy efficiency. Finally, based on the conclusion, this paper puts forward the policy suggestion of promoting the energy efficiency of the urban agglomeration in the Yangtze River Delta. [ABSTRACT FROM AUTHOR]

Abstract Under the background of energy and environmental pressure, the traditional automobiles directly driven by fossil fuel-based internal combustion engines are facing elimination. Extended-range electric vehicles (EREVs) charged by small internal combustion engines become an alternative choice because EREVs have longer range and higher efficiency than battery-based electric vehicles, such as lithium battery-based vehicles. However, most EREVs still utilizes fossil fuel-based internal combustion engines, which still have significant carbon footprint. To compromise this downside, this paper proposes a hydrogen fuel cell extended-range electric vehicle design using liquid ammonia as hydrogen source, and quantify the energy and materials flows for the design. This paper establishes a conceptual model of the entire vehicle taking a truck as an example. A typical configuration is selected to perform energy flow balance calculation. The dynamic model of the vehicle is further constructed based on the conceptual model. Based on the performance requirements of the vehicle's driving, parameters were determined for the motor system, fuel cell system, battery system and super capacitor system. [ABSTRACT FROM AUTHOR]

Abstract The objective of this paper is to assess the impact on fuel saving and emission reduction of biodiesel for power generation, using a wide range of economic indicators. There are many benefits that countries, especially developing ones can gain from renewable fuels like biodiesel. Apart from the possibilities that opens for economic growth and development across the country, especially for rural communities; opportunities are available for independent power producers to generate power to off-grid users and local businesses. This is only achievable from engines and fuels with good economic performance. This paper analyse the impact of Callophyllum inophyllum (CI) biodiesel on the fuel saving and the carbon dioxide (CO 2) emission reduction, focusing on the application of CI biodiesel in two different systems, namely internal combustion engines in the transport sector and gas turbines in the power sector. The results showed that application of CI biodiesel in the power sector is able to have more significant savings in fuel and reduction in the CO 2 emissions. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a hybrid subjective and objective evaluation method of the equipment for first-class distribution network. Firstly, it analysis the difficulties of the equipment selection in the current first-class distribution network. Secondly, it deeply analysis the influencing factors of equipment selection in the first-class distribution network. The comprehensive evaluation indices system of first-class power distribution network equipment is constructed from five aspects including economy, performance, intelligence, coordination, and standardization of equipment, in order to the features of the equipment for power distribution network, such as diversity of equipment functions, diverse evaluation indicators, various types, and varied access methods. The subjective weighted methods are highly subjective and difficult to fully express the effectiveness of weights for evaluating indicators. The objective weighted methods are easy to lose key information due to limited sample of measurement data. A hybrid subjective and objective weighting method is proposed to combined with principal component analysis and analytic hierarchy process, and the relative entropy principle is used to weight distribution of subjective and objective evaluation results. Finally, the feasibility of the proposed method is verified through the first-class distribution network equipment in a province in southern China. This paper provides reference for comprehensive evaluation of first-class distribution network equipment. [ABSTRACT FROM AUTHOR]

Abstract This paper aims to give comprehensive review on the state of current researches and provide some reference for future research. For this purpose, the paper firstly analyses the evolution of real option theory and method, following with the characteristics of renewable energy investment. Then, the usability of real option to renewable energy investment is discussed, and the diverse applications of real option on renewable energy investment and policy evaluation are conducted. The directions for future researches are also presented in the end. [ABSTRACT FROM AUTHOR]

Abstract Nowadays different kinds of renewable energy resources have got rapid development. For renewable energy planning, it is meaningful to assess the comprehensive performance of different candidate renewable energy schemes and distinguish the optimal. In view of this, based on data envelopment analysis(DEA), this paper presents a comprehensive evaluation method of renewable energy technical plans. Firstly, multiple indexes from different aspects are taken into consideration to establish the index system. And in the index processing stage, intuitionistic fuzzy number theory is adopted to describe the fuzziness and ambiguity in qualitative index and convert it into quantitative calculation. Then, super-efficiency DEA model is used to determine the relative ranking of different plans based on the concept of relative efficiency. Finally, a real case of renewable energy development in 2020 from a province in China is used to illustrate the feasibility and effectiveness of the proposed method in this paper. Results show that this proposed method can overcome the shortcoming of traditional basic DEA model and get more objective evaluation results and provide beneficial references for renewable energy planning and development. [ABSTRACT FROM AUTHOR]

Abstract Renewable energy can reduce greenhouse gas emissions by providing renewable electricity, heating, cooling and transportation. The main disadvantage of renewable energy supply is that once it reached a high share in electricity generation, the intermittency caused by renewable energy sources makes balancing of the energy system challenging. This study answers the question "What is the impact of renewable energy on public investment in R&D of energy storage technologies?" Empirical literature studying investments in renewable energy technologies is abundant, however empirical literature studying investments in energy storage technologies is highly limited. Using annual panel data from 28 OECD countries over the period 1990-2014 this paper provides an empirical evidence on the role of renewable energy deployment on public investments in energy storage technologies. The results of fixed effects estimation provide an empirical evidence that governments from countries with greater share of renewable energy invest more in energy storage technologies. Drawing from the empirical results, this paper provides policy recommendations on the need in investments in energy storage technologies due to a growing supply of renewable energy. Although this paper provides lessons from countries which experienced problems with high share of renewable energy and started to promote energy storage alongside with renewable energy, the results will be useful for policy-makers from developing countries with a growing share of renewable energy in total electricity. [ABSTRACT FROM AUTHOR]

Abstract The year 2020 will be the first year for global stocktake on carbon mitigation, whether the current policies are on track to meet the NDC goals would become a highly focused issue, and further enhancement on national NDCs under long-term climate mitigation target would also attract much attention by then. Comparing the actual CO2 emissions in 2017 and the expected emissions under NDC goals, this paper analyzes the gaps between current mitigation progress and NDC goals for major region including the US, EU, China and India, and energy system optimization has been conducted to explore possible plans to close these gaps. In addition, this paper compares CO2 emission pathways under global NDCs and 2-degree target, pointed that existing NDCs are not enough to realize 2-degree target, by 2030, additional mitigation of about 10 Gt CO2 is required for global energy system, which indicating enhanced NDCs should be designed as soon as possible to reduce risks and cost in long-term mitigation actions. [ABSTRACT FROM AUTHOR]

Abstract IMO issued latest environmental regulations Tier Ⅲ has strengthened the emission standards, in which the NOx emission should be less than 3.4g/(kWh) for marine two-stroke engines (engine speed lower than 130r/min) in NOx ECAs. In order to meet the strengthened emission regulations, EGR and fuel injection strategies have been used in marine two-stroke engines to reduce emissions. In this paper, a full cycle computation fluid dynamics (CFD) simulation model has been established in GT-Power software to study the effects of EGR rate, post-injection and pilot-injection on emissions and overall performance of a low speed two-stroke marine engine. By changing the EGR rates and the degree and mass of the post-injection and pilot-injection, an optimal combination among different fuel injection strategies and EGR rates is proposed in this paper. The results indicate that the degree and mass of injection strategies with EGR play an important role in NOx and soot emissions. The trade-off relationship between NOx and soot is improved by changing the fuel injection strategies with different EGR rates. [ABSTRACT FROM AUTHOR]

Abstract As the major energy consumer and carbon emitter, the power sector accounts for 40% of total carbon emissions in China in 2011. Understanding provincial-level driving mechanisms of CO 2 emissions in power sector is vital for achieving China's national carbon emissions reduction targets in 2030. To understand the critical provinces and driving forces of CO 2 emissions in power sector, this paper firstly derives seven different driving factors based on the logarithmic mean Divisia index (LMDI) decomposition model. The provincial-level CO 2 emissions in thermal power sectors are calculated from 2004 to 2014. Then, we analyze the CO 2 emissions growth ratio of each province, provincial-level change rate of contribution and positive or negative contributions of the emission dynamics for each driving force. The main results show that the power sector of Inner Mongolia and Jiangsu contribute a lot to national CO 2 emissions. The change of CO 2 emissions of power sector is bigger in developing provinces compared to that in developed provinces. Based on provincial the CO 2 emissions changes and total amounts, more carbon emission reduction policy should be implanted in Inner Mongolia, Xinjiang, Anhui, Jiangsu and Ningxia. In addition, the economic scale, industrial intensity and energy intensity are the critical driving forces for total carbon emission. By investigating the critical driving forces and their contributions in critical provinces, this paper aims to provide theoretical foundations for decarbonizing power sector. [ABSTRACT FROM AUTHOR]

Abstract On-load tap changer (OLTC) plays a significant role to regulate the voltage of the power system. Although some time, secondary voltage of an OLTC is pulled down when tappings are raised to restore the voltage level. This situation may finally lead to voltage collapse. To address this problem, the behavior of tap setting of OLTCs is investigated, and critical transformer and its allowed range of tap settings is identified in the paper. This paper also proposes a Taguchi based method to find optimal tap settings of OLTCs including critical transformer to improve the voltage stability margin and decrease the real power loss of the system. The proposed method is tested on IEEE 30-bus system to validate its applicability. [ABSTRACT FROM AUTHOR]

Abstract For the past two decades, extensive research has been conducted to evaluate the performance of urban form scenarios such as sky view factors, solar radiation, or energy performance. Simulation-based performance analysis has been applied for optimizing urban design using multiple performance criteria of energy demands, daylighting, or radiance. Two major limitations exist in the performance evaluation methods of urban design: 1) the number of urban design alternatives or scenarios has been limited, and 2) various performance criteria and metrics have not been assessed synthetically. In this respect, we aim to generate all possible alternatives under constraints such as a city policy or development requirements. This paper addresses the integration of generative design and multi-criteria performance analysis for urban design decision making. The relationships between geometric urban forms and multiple performance criteria are identified. The proposed methodology incorporates the reinforcement learning algorithm, an advanced machine learning technique, along with parametric modeling techniques, to enhance urban design decisions based on various performance criteria. This methodology was tested on the design of an international campus of the Georgia Institute of Technology, located in Shenzhen, China. An algorithm generates numerous geometrical alternatives of campus design under site constraints and development requirements of the campus. Those alternatives are then evaluated based on performance criteria of sky openings, solar radiation, or energy consumption synthetically. The method enables an integrated performance analysis for all possible design under constraints. The paper proposes a data driven urban design approach that connect generative design and multi-criteria performance analyses. The relationships between urban geometric forms and performance criteria function derive guidelines for a sustainable and green campus. In future conduct multivariate analysis to examine the relationships between geometric elements and performance measurement metrics. [ABSTRACT FROM AUTHOR]

Abstract By constructing a dynamic spatial Durbin model based on C-D production function that includes energy consumption and air pollution, this paper explains the driving factors of urban economic output in the "2+26" cities of Beijing-Tianjin-Hebei and its surrounding areas during 2006-2015. The result shows the significant spatial autocorrelation of energy consumption and air pollution in the "2+26" cities. The increase in economic output of neighbouring cities will bring about economic radiation and promote the economic output of the city, which provides strong evidence for the necessity of joint prevention and control policy. Further considering effects of the inputs of neighbouring cities, the paper finds that the driving force of economic increase mainly came from the capital and energy input of the city itself, as well as the air pollution dividends of neighbouring cities. Therefore, Beijing-Tianjin-Hebei and its surrounding areas should make the best of the resource advantages of neighbouring cities to achieve complementarity and coordinated development. Governments should construct comprehensive cross-city air pollution prevention mechanism, such as regional air pollution compensation mechanism and fund for air pollution joint control. [ABSTRACT FROM AUTHOR]

Abstract Shipping is a major contributor to the global CO 2 emissions. In order to reduce the ship emissions, various mitigation strategies have been proposed including technical and operational strategies. As it is usually not possible to implement all these mitigation strategies, it is important to evaluate the efficiency of these strategies. For mitigation strategies evaluation, ship energy systems are often used for assessment from a systems perspective. However, ship energy systems are usually quite complex for analysis. This is because they are constructed by many components and these components may have non-linear correlations. In this paper, a Gaussian process metamodel based method is proposed to evaluate the ship mitigation strategies. This method is much more efficient than directly analyzing the ship energy systems when they are computationally expensive to assess. A ship energy system of a chemical tanker is analyzed in this paper. The results indicate that speed reduction has a large abatement potential and all the considered strategies have correlations with each other. [ABSTRACT FROM AUTHOR]

Abstract The paper reviews the processes of Geodesign, as it is currently used in practice, and explore its capability and limitation to adapt to new smart city design and technology. Predictions about the future city are being attempted based on data that is for all intents and purposes based on the distant past. In the smart city, where data is both ubiquitous and continuous, it is possible to use metadata to quickly gain an understanding of how the future city is designed and how the current urban system can be altered. Existing building energy data of eight housing units in the Sumida neighborhood of Tokyo was collected using smart meters. This data was analyzed to determine how the buildings perform in real-time, compared to how the energy models predict the building performance. This comparison showed that the existing buildings are using more energy than the current models predict. There is potential that better utilizing data can help designers and planners come closer to meeting community goals. There is also potential that as we integrate more smart city technologies into our cities for improving future city model, or the change model in Geodesign. This paper discussed how other variables that can be incorporated into larger-scale problems, in which an object-oriented city design model is proposed based on a network of objects and multiple system boundaries. [ABSTRACT FROM AUTHOR]

Abstract Thermal energy storage (TES) has a crucial role to play in conserving and efficiently utilising energy, dealing with mismatch between demand and supply, and enhancing the performance and reliability of our current energy systems. A competitive TES technology requires a number of scientific and technological challenges to be addressed including TES materials, TES components and devices, and integration of TES devices with energy networks and associated dynamic optimization. This paper concerns mainly about TES materials challenges with a specific focus on using shape stable composite phase change materials (CPCMs) for medium and high temperature application. The paper first briefly reviews the state-of-the-art development of materials research for thermal energy storage. The focus is then on CPCMs for medium to high temperatures applications, covering materials screening, formulation based on molecular modelling validated at a different length scale through experiments, formulation based on chemical and physical compatibility, and manufacture of material modules via innovative use of conventional powder technology. The properties of the materials and materials modules are characterised and analysed with an aim to establish property-structure relationships. This includes a particularly interesting aspect of the motion of PCM and nanoscale objects with the PCMs for heat transfer enhancement during thermal cycling, which explains the mechanisms of the encapsulation of PCMs in the composite. [ABSTRACT FROM AUTHOR]

Abstract This paper reviews different methods for determination of specific heat capacity of lithium-ion batteries. Thermal modelling of lithium-ion battery cells and battery packs is of great importance. The specific heat capacity of the battery is an essential parameter for the establishment of the thermal model, and it is affected by many factors (such as SOC, temperature, etc.). The scientific purpose of this paper is to collect, sort out and compare different measurement methods of specific heat capacity of battery. The advantages and disadvantages of different methods are discussed. The applicability of each measurement method for various battery types and the required experimental conditions are discussed. The factors influencing the specific heat capacity of the battery are also summarized. [ABSTRACT FROM AUTHOR]

Abstract In China, renewable energy is expected to account for a larger proportion of electric power systems although regional and intermittent characteristics have led to enormous unused wind and solar power stations in western and northern China. In the mean-while, there exists a large demand on energy in central and eastern areas. The energy storage capability of hydrogen makes it a significant medium for emerging energy storage systems. But the formidable challenge of hydrogen storage and long-distance transportation restricts its development. To address this issue, this paper proposes a scheme for an ammonia-based energy storage system in which ammonia, an environmentally benign hydrogen carrier, is expected to compromise the conflicts of renewable energy supply and consumption in China. By utilizing abandoned wind power and solar power, we get electrolyze water to generate hydrogen and get air to generate nitrogen. Compositing ammonia with hydrogen and nitrogen using Hubert's method also need much electricity. And the power stored in ammonia can be released in form of thermal energy or electricity when needed. This paper then presents some typical applications of ammonia that can meet people's needs of fuel, power, electricity, and zero-carbon fertilizer. The proposed scheme is particularly useful for storing discarded power in western and northern China in ammonia which can be transported and used in eastern regions without regional and seasonal restrictions. As an extra advantage, oxygen as a side product associated with the production of ammonia may play a significant role in oxygen-riched combustion plants. [ABSTRACT FROM AUTHOR]

Abstract The temperature of exhaust gas can exceed 800K, which is much higher than surroundings. It's easy to demonstrate IR and get bombed. Therefore, it's necessary to lower the temperature of exhaust gas. In this paper, a kind of infrared suppressor which uses engine exhaust to eject cold air and water spray is designed. Water spray is produced by ultrasonic atomization. The mixing process of the ejector is revealed by CFD. CFD results are validated with the experimental values. After validation is satisfied, this paper analyzes the temperature field inside the ejector and compares the performances of ejectors with varying geometries. According to CFD results, a device is made. Test results show that a good performance is achieved: radiation energy is only 36% of the original. [ABSTRACT FROM AUTHOR]

Abstract Quantum dots (QDs) are the potential material for the application in optical thermometry, and have been successfully applied to solar cells, LEDs, bio-labeling, structural health monitoring, etc. In this paper, we study the fluorescence properties of CdSe/ZnS QDs in toluene under the action of heating-cooling cycles. The experimental results show that, in a heating-cooling cycle, increasing temperature causes red-shift of the emission peak and the decrease of the PL intensity, and decreasing temperature causes blue-shift of the emission peak and the increase of the PL intensity. The surface structures of the QDs likely are dependent on the cycle numbers, which cause the change of the excited energy state of the QDs in toluene. The results presented in this paper reveals the strong effects of cyclic temperature on the photoluminescence characteristics of QDs. [ABSTRACT FROM AUTHOR]

Abstract This paper introduces the similarity between the mechanism of carbon trading and blockchain, then it elaborates on the application of blockchain in carbon trading. In corporate carbon trading, blockchain technology can record and transfer information flow reliably, realize point-to-point transactions between suppliers and demanders to achieve "decentralization", help to reduce the entry threshold for the carbon trading market. At the same time, an analysis of social environment for blockchain-based carbon trading on person is made. Finally, the paper confirms the value of "blockchain + carbon trading" and looks forward to the future. [ABSTRACT FROM AUTHOR]

Abstract To match for the different temperature of the geothermal resource and strengthen the flexibility of organic Rankine cycle (ORC), this paper proposes a variable capacity power generation superstructure based on Flash and ORC for geothermal energy. A combined Flash-ORC experimental prototype is established to investigate its performance on both steady and dynamic conditions in this paper. Pressured hot water is adopted as the extensive worldwide existed hydrothermal geothermal resource, eliminating the influence of the used heat transfer oil on evaporating process. The experiment results show that there is an optimal mass flow rate of R245fa under the condition of different heat source temperature; Flash and binary power system dominate the flash-binary power system respectively when the heat source temperature are 120 ℃and 130℃;The isotropic efficiency of modified compressor just between 0.2 and 0.25; the power output of per geofluid mass flow rate are 0.78 kWh·t-1and 1.31 kWh·t-1 respectively when the heat source temperature are 120 ℃and 130℃. [ABSTRACT FROM AUTHOR]

Abstract Wind power, solar power and hydropower can form a good complementary effect in space and time. Research on Wind-Solar-Hydro power generation system has gradually become a hot research topic. In this paper, a large-scale hydropower station in southwestern China and its surrounding wind fields and solar fields are taken as examples to establish an optimal scheduling model with the objectives of maximizing system total power generation, maximizing the minimum monthly joint output of the whole scheduling period, and minimizing the ecological over-and-short discharge. The paper presents a multi-objective dragonfly algorithm base on reference point to obtain the non-dominated solutions in the wet year, normal year and dry year. Meanwhile, the scheduling processes of four representative plans on the obtained Pareto front are selected to analyze its certain practical significance. It is found that the established multi-objective optimal model and the proposed algorithm have certain reference value for the optimal operation of Wind-Solar-Hydro power generation system. [ABSTRACT FROM AUTHOR]

Abstract In this paper, based on the study of the effect of indoor natural ventilation, application of earth-air heat exchanger cooling technology in an office was investigated. Taking an office building in Jinan City as an example, this research analyzed the performance of interactions between earth-air heat exchanger cooling technology and building indoor thermal environments. Indoor thermal environment was analyzed with numerical simulation of computational fluid dynamics, the Airpak software was applied for numerical calculation to gain the indoor temperature field, velocity field and the distribution of the PMV index. In addition, energy utilization efficiency was also analyzed in this paper; results showed that reasonable airflow organization is a significant content in airflow design of office rooms under the small temperature difference of earth-air heat exchanger conditions. This will provide basic reference for design of earth-air heat exchanger cooling system. [ABSTRACT FROM AUTHOR]

Abstract Generally, the hourly average wind speed is used in determining the spare capacity and real-time dispatch in power system, but the actual wind speed on the wind turbine is the actual instantaneous wind speed. An indicator (instantaneous variance) that quantify the variability of wind speed (WS) and wind power (WP) is used in this paper, and the experiments prove the rationality of it. Meanwhile, the relationship between the fluctuation of WS and the fluctuation of WP is discussed by using local maximum and minimum points distributions. According to the methods mentioned in this paper, the index applied to quantification of fluctuation is applicable to the schedule of system spinning capacity and the strong consistency of the fluctuations of WS and WP has been proved. [ABSTRACT FROM AUTHOR]

Abstract To realize the commercialization of SOFC, it must be ensured that it can work efficiently and stably. SOFC fault diagnosis becomes an essential part of the research. Due to the strong coupling of faults in the stack, this paper uses neural network algorithm to detect and diagnose faults. The simulation results verify that through the diagnosis of the test sample, the recognition rate of the test sample by the network is found to be 95%, which explains the neural network fault diagnosis model established in this paper on identifying the normal working state of the stack, the electrode stacking of the stack, and the gas leakage fault of the stack has good effectiveness and accuracy. [ABSTRACT FROM AUTHOR]

Abstract The admittance model for the three-phase AC micro-grid is proposed in the paper considering the imbalance of the local load and active compensation of the multi-functional grid-connected inverter (MFGCI). By adopting complex variables, the model unified the positive-sequence and negative-sequence admittances for both the grid-connected inverter and the load. Moreover, the dq transformation based imbalance compensation algorithm is integrated into the model according to the harmonic linearization principle. The theoretical analysis and simulation verify the accuracy of the proposed admittance model. The analysis also indicates that while the adoption of the active compensation can decrease the imbalance of the system, the magnitude and phase characteristics of the equivalent admittance of the compensated load are significantly changed. The admittance model proposed in this paper can be the foundation work for the system stability study for the AC micro-grid. [ABSTRACT FROM AUTHOR]

Abstract Solid oxide fuel cell is a device that can convert chemical energy directly into electricity. Its advantages, such as high efficiency, low emission, quiet operation, fuel flexibility, bring about the broad application prospect. However, it is difficult to obtain the temperature distribution in the existing planar cross flow solid oxide fuel cell through the experiment. In this paper, a control orient two-dimensional differential equation model is established for a planar cross flow solid oxide fuel cell based on the finite node method, and an iterative algorithm for calculating the real time voltage of the fuel cell is proposed for the model. Based on the model, the temperature distribution of the fuel cell in the test and system configuration is simulated. The simulation results show that the model can reflect the thermoelectric characteristics of the planar cross flow solid oxide fuel cell, especially the temperature distribution of the fuel cell. The SOFC temperature distribution modeling in this paper is helpful for the development of temperature distribution observers and design related control methods in later studies. [ABSTRACT FROM AUTHOR]

Abstract This paper describes an integrated power unit (IPU) supplying bleed air and shaft power for main engine starting, aircraft environment control, and in-flight emergency power demand. The zero-dimension steady-state numerical simulation model of the IPU is built for both the normal air breathing (NAB) mode and the stored energy (SE) mode. The design point of the IPU is set in the NAB mode and the off-design performance calculations are accomplished for both modes. The Altitude-Mach characteristic of the NAB mode and the altitude characteristic of the SE mode are discussed and the fundamental control laws of the SE mode are established to minimize stored air consumption. The overall efficiency of the IPU is illustrated in the paper for the two modes. [ABSTRACT FROM AUTHOR]

Abstract The diversity of both organic fluids and performance criteria makes the selection and evaluation of working fluids for organic Rankine cycles (ORCs) full of challenge. To overcome this challenge, this paper first reports on second-law-based analytical expressions for thermal efficiency and a turbine size parameter, which reveal key dimensionless parameters relating to operating temperatures and thermodynamic properties of organic fluids. This paper systematically screens more than 70 working fluids involving a wide range of physical and chemical properties. This study shows that specific turbine size generally increases with critical temperature, reduced ideal gas heat capacity, and the atom number of working fluids. Different-family fluids may lead to ten-fold relative differences in specific turbine size even though they have the same atom numbers. The thermal efficiency of ORCs appears to be independent of critical temperature, or at most, a weak function of critical temperature for low boiling point wet fluids and other halocarbons. This is a result of Jacob number being independent of or dependent weakly on the critical temperature of organic fluids such as alkanes, alkenes, and benzenes. [ABSTRACT FROM AUTHOR]

Abstract Air pollution and increased CO 2 concentration in atmosphere and other energy related issues caused a transformative shift in energy system which contributes to increased utilization of renewables as alternative to generate green energy carriers. The potential of renewable resources in different region and potential energy conversion have been largely considered by many researcher in many countries. The energy conversion technologies to produce heat, electricity, and transportation fuels have made impressive technical advances. Sweden has also been challenging with mitigation of CO 2 emission and trying to shift into a fossil fuel free system in all energy sectors. This paper deals with the current status of fuel demand and supply in the transport sector in a County in Sweden. A scenario for a fossil fuel free transport sector at a regional level is developed to investigate the potential biofuel production from regionally produced straw. The results and analysis indicate that the potential for cereal based bioethanol production in the region is sufficient to meet the biofuel demand of the County. Using the fallow land for cereal cultivation, it is feasible to shift into a fossil fuel free transportation system where all passenger cars are fueled by bioethanol. The results and finding from the current paper will be used to develop further study on optimization of local biofuel production integrated with CHP plants considering application of other feedstock such as municipal wastes. [ABSTRACT FROM AUTHOR]