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The energy conversion efficiency of coal utilization is a focal point in modern energy management practices and in academic literature. This paper explores life cycle energy efficiency of coal (LEEC), which encompasses six distinct stages from the design of coal mines to the comprehensive reuse of resources. First, the study analyzes improvements to the evaluation of efficiencies in energy systems. Secondly, it proposes a multi-stage energy efficiency analysis and constructs an innovative LEEC model for coal exploitation and utilization. Thirdly, the energy efficiency of coal exploitation and utilization was evaluated, and found that total efficiency in China increased from 33.11% in 2010 to 37.69% in 2014, saving 126 Mtce of energy. Finally, this study found that mine design is the most important stage in improving energy efficiency, followed by the coal processing stage. Moreover, we found that coal processing has an indirect contribution to other stages in the life cycle utilization of coal, such as reducing transportation capacity. The primary research contribution is the development of a comprehensive LEEC model for the entire life cycle of coal, rather than just single-stage evaluation. This lays the foundation for further studies on energy efficiency of industrial chains and across entire systems. • Exploration of energy efficiency across the entire coal life cycle. • The energy efficiency of coal exploitation and utilization increased annually. • Analysis shows the implicit contribution of coal processing to life cycle. • Mine design is a crucial stage for overall life cycle energy efficiency. [ABSTRACT FROM AUTHOR]

As the physical subject, determining vehicle operating modes is a prerequisite for implementing global optimization energy management. To avoid the case study of different vehicle configurations, a "kinetic/potential energy & onboard energy" conservation framework is proposed to determine vehicle working modes. Firstly, typical topologies and existing work modes for hybrid vehicles with different architectures are summarized. As a numerical method, the state space is meshed, which is restricted by introducing trip information. Then, a "kinetic/potential energy & onboard energy" conservation framework is established to determine the work mode between any reachable state points. By combining external factors, internal factors and additional factors reasonably and feasibly, various trigger conditions are generated to realize the one-to-one mapping between work mode and driving condition, which standardizes the DP optimizing process. Correspondingly, the stage cost and control are determined to achieve the optimal energy distribution. Finally, regarding DP strategy as a benchmark, multiple evaluation indexes are proposed to evaluate the utilization ratio of a control strategy to global trip information. An example is given to evaluate the optimal rule-based strategy. The higher the index is, the higher the similarity with the DP strategy is, and the higher the economic performance of the vehicle is. • An energy conservation framework is established to determine work modes. • An efficient global optimization algorithm is proposed. • Multiple indexes are proposed to evaluate the energy-saving potential. [ABSTRACT FROM AUTHOR]

Abstract: A survey of the key issues associated with the development in the Chinese iron and steel industry and current situations of energy consumption are described in this paper. The apparent production of crude steel in China expanded to 418.78 million tonnes in 2006, which was about 34% share of the world steel production. The iron and steel industry in China is still one of the major high energy consumption and high pollution industries, which accounts for the consumption of about 15.2% of the national total energy, and generation of 14% of the national total wastewater and waste gas and 6% of the total solid waste materials. The average energy consumption per unit of steel is about 20% higher than that of other advanced countries due to its low energy utilization efficiency. However, the energy efficiency of the iron and steel industry in China has made significant improvement in the past few years and significant energy savings will be achieved in the future by optimizing end-use energy utilization. Finally, some measures for the industry in terms of the economic policy of China''s 11th five-year plan are also presented. [Copyright &y& Elsevier]

Abstract: One vital means of raising energy efficiency is to introduce district heating in industry. The aim of this paper is to study factors which promote and inhibit district heating collaborations between industries and utilities. The human factors involved showed to affect district heating collaborations more than anything else does. Particularly risk, imperfect and asymmetric information, credibility and trust, inertia and values are adequate variables when explaining the establishment or failure of industry-energy utility collaborations, while heterogeneity, access to capital and hidden costs appear to be of lower importance. A key conclusion from this study is that in an industry-energy utility collaboration, it is essential to nurture the business relationship. In summary, successful collaboration depends more on the individuals and organizations involved in the relationship between the two parties than on the technology used in the collaboration. [ABSTRACT FROM AUTHOR]

A novel multimode power-split hybrid electric vehicle demonstrates significant advantages in energy conservation. The complicated structure and multiple operation modes, however, have brought significant challenges to energy management. The problems of operation mode selection, power allocation, and operating point selection need to be solved simultaneously. Traditionally, existing energy management strategies first have determined operation mode and then have solved power allocation and operating points. Moreover, traditional dynamic programming usually has not considered electric energy consumption and has deviated from the optimal solution. To solve these problems, a cascaded energy management strategy that integrates dynamic programming and equivalent consumption minimization strategy (DP + ECMS) is proposed. An iterative method is used to optimize the equivalence factor. A vehicle model based on actual control strategy is established and validated by test results. Then fuel economy simulations are conducted. Results showed that DP + ECMS could achieve 19.9% fuel economy improvement compared with the rule-based strategy for a new European driving cycle. In addition, simulation results of a Worldwide Harmonized Light-Duty Test Cycle demonstrated that DP + ECMS performed well in real road driving conditions. This study introduces a novel multimode power-split hybrid system and provides a global energy management optimization method. Image 10601 • A novel multimode power-split hybrid system is introduced. • A vehicle model based on actual vehicle control strategy is developed and validated. • Operation mode, power allocation, and operating points are optimized simultaneously. • A cascaded optimization method that integrates DP with ECMS is adopted. • An iterative method is used to optimize the equivalence factor. [ABSTRACT FROM AUTHOR]