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Energy storage is nowadays recognised as a key element in modern energy supply chain. This is mainly because it can enhance grid stability, increase penetration of renewable energy resources, improve the efficiency of energy systems, conserve fossil energy resources and reduce environmental impact of energy generation. Although there are many energy storage technologies already reviewed in the literature, these technologies are currently at different levels of technological maturity with a few already proven for commercial scale application. Most of the review papers in energy storage highlight these technologies in details, however; there remains limited information on the real life application of these technologies for energy storage purpose. This review paper aims to address this gap by providing a detailed analysis of real life application and performance of the different energy storage technologies. The paper discusses the concept of energy storage, the different technologies for the storage of energy with more emphasis on the storage of secondary forms of energy (electricity and heat) as well as a detailed analysis of various energy storage projects all over the world. In the final part of this paper, some of the challenges hindering the commercial deployment of energy storage technologies are also highlighted. [ABSTRACT FROM AUTHOR]

• Method for making time series data samples of imitation pictures. • Calculation model of reasonable line loss interval in transformer area based on CNN. • A new self-adaptive evaluation system of line loss index. • Lean management strategy of line loss in distribution transformer area. As the wiring of distribution network becomes more and more complex, it is difficult to calculate the theoretical line loss of low-voltage distribution transformer area and the evaluation index of transformer line loss is extensive. In this paper, a reasonable interval calculation model of line loss is established based on the data of electricity information acquisition system. Firstly, the collected data are processed in the image format, and then the line loss calculation model is established based on the convolutional neural network. This model can estimate the reasonable line loss interval according to the operation data of different transformers. On this basis, the line loss evaluation system is established and the loss reduction strategy of abnormal transformer is formed. The method in this paper can be used to evaluate the line loss level of distribution transformer area more accurately. It also can improve the quality and efficiency of line loss lean management and produce certain effect for electric energy conservation and improving economic benefit of power supply. [ABSTRACT FROM AUTHOR]

Highlights • Parameters of 60 electricity-saving measures and 16 abatement measures are compiled. • Synergies of electricity use in China's chemical sector at grid level are assessed. • Efficient use of power can cut 154 Mt CO 2eq , 295 kt SO 2 , 322 kt NO x and 64 kt PM 2.5. • North and Northwest grids have the largest economic benefits on emissions reduction. • Grid with high electricity price is more sensitive to price change than other grids. Abstract Industry is a large electricity user. China's chemical industry (globally the largest based on sales) contributes 7% to China's GDP, while it consumes 11% of the total electricity consumption in industry and is responsible for 40% of total CO 2eq , 40% of SO 2 , 59% of NO x and 18% of PM-emissions of the chemical industry emissions. The heterogeneity of GHG and air pollutant emissions across electricity grids (within a country) is rarely included in analyses. In this paper, electricity conservation supply curves are developed (distinguishing the grids) to estimate the cost-effective and technical potentials of electricity conservation in China's chemical industry. The emission factors per grid for GHG (i.e. CO 2 , CH 4 and N 2 O) and air pollutants (i.e. SO 2 , NO x and PM 2.5) are calculated and used to quantify the emissions mitigation achieved by electricity saving technologies in the chemical industry for the period 2012–2035. Results show that significant multiple benefits can be obtained by implementing electricity efficiency measures. There are large differences among the six grids in terms electricity savings and emissions abatement of GHG and air pollutants. 83% of the total electricity saving potential is contributed by the North, Northwest and Central grids, equal to 32% of baseline electricity consumption in 2035. In 2035, 129 Mt of CO 2 , 33 kt CO 2eq of CH 4 , 571 kt CO 2eq of N 2 O, 235 kt of SO 2 , 275 kt of NO x and 52 kt of PM 2.5 in these three grids can be avoided as a result of electricity savings (a reduction of 31–33% compared to baseline emissions). When decision-makers set targets for energy saving and emission reduction, the multiple benefits and grid heterogeneity should not be ignored. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes the principles of how to define a boundary for heat integration in petrochemical complexes which are composed of several interconnected processing units. In order to obtain retrofit schemes that offer significant energy saving potential and are easy to implement, heat integration strategies are also developed in this study. Two case studies based on an aniline plant and an aromatic hydrocarbon plant, each one comprising several processing units, are presented to illustrate the application of these principles and strategies. The boundary for heat integration in each plant can be the whole plant or its individual processing units, the choice of which is determined by their energy saving potentials. Based on energy saving potential, each processing unit in the aniline plant was selected as the boundary for heat integration. The boundary for heat integration in the aromatic hydrocarbon plant, by contrast, was the whole plant. Retrofit schemes for the heat exchanger networks of the two plants, developed using pinch analysis, revealed that significant heating utility savings could be realized with a small number of network structure modifications. [Copyright &y& Elsevier]

Abstract: Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO2 emitting country in the world. In this case, the inappropriate energy consumption structure should be changed. As an alternative, a suitable infrastructure for the implementation of renewable energy may serve as a long-term sustainable solution. The perspective of a 100% renewable energy system has been analyzed and discussed in some countries previously. In this process, assessment of domestic renewable energy sources is the first step. Then appropriate methodologies are needed to perform energy system analyses involving the integration of more sustainable strategies. Denmark may serve as an example of how sustainable strategies can be implemented. The Danish system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy system. The conclusion is that China’s domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system in China is not unreasonable. [ABSTRACT FROM AUTHOR]

Abstract: One of the central variables in bottom-up energy efficiency and saving calculations is the energy consumption baseline. In the evaluation of energy efficiency measures, developing this baseline is a challenging task, which may involve serious problems, especially if the energy service of the analysed subject has changed while the energy efficiency measure was being implemented. In this paper we present a formalised concept of the process of developing the baseline that is flexible enough to deal with various difficulties, such as changes in the levels of the energy services involved. We also discuss the most relevant options for deriving the necessary variables. [ABSTRACT FROM AUTHOR]

Abstract: Greenhouse gas mitigation strategies are generally considered costly with world leaders often engaging in debate concerning the costs of mitigation and the distribution of these costs between different countries. In this paper, the analyses and results of the design of a 100% renewable energy system by the year 2050 are presented for a complete energy system including transport. Two short-term transition target years in the process towards this goal are analysed for 2015 and 2030. The energy systems are analysed and designed with hour-by-hour energy system analyses. The analyses reveal that implementing energy savings, renewable energy and more efficient conversion technologies can have positive socio-economic effects, create employment and potentially lead to large earnings on exports. If externalities such as health effects are included, even more benefits can be expected. 100% Renewable energy systems will be technically possible in the future, and may even be economically beneficial compared to the business-as-usual energy system. Hence, the current debate between leaders should reflect a combination of these two main challenges. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the analysis and comparison of the main active techniques for islanding detection used in grid-connected microinverters for power processing of renewable energy sources. These techniques can be classified into two classes: techniques introducing positive feedback in the control of the inverter and techniques based on harmonics injection. Accurate PSIMTM simulations have been carried out in order to perform a comparative analysis of the techniques under study and to establish their advantages and disadvantages according to IEEE standards. [ABSTRACT FROM AUTHOR]

Abstract: In the last years, the growing demand for air conditioning has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the technologies which allows to obtain, by using the renewable solar source, an important energy saving compared to traditional air conditioning plants. The paper describes different technical installations for solar cooling, their way of operation, advantages and limits. The objective of the present study has been to analyze the technical and economic feasibility of solar absorption cooling systems, designed for two different application fields: industrial refrigeration and air conditioning. The possibility to replace or integrate the existing plants is studied, by considering the refrigeration requirements of a company, which works in meat manufacturing, and the heating and cooling demands of a hotel located in a tourist town in Italy. In the first case, the system comprises an absorption chiller coupled to solar flat plate collectors, whereas the second application is about a hybrid trigeneration plant, known as thermo-solar trigeneration; this option allows having greater operational flexibility at sites with demand for energy in the form of heating as well as cooling, for example in a hotel. In this way the authors could compare different results obtained by a technical and economic experimental analysis based on existing users and evaluate the advantages and disadvantages in order to suggest the best solution for the two studied cases. [Copyright &y& Elsevier]

This paper describes a numerical approach to power-loss minimization in a fractional hp induction motor driven by a voltage-source inverter. The motor parameters are obtained from a genetic algorithm search. Optimum voltage and frequency excitations are arranged as a table for an energy-saving controller. The proposed method is useful under variable-torque load conditions. Simulation and experimental results are presented. [Copyright &y& Elsevier]