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Abstract: The use of groundwater for cooling and heating purposes is of interest from both the economical and the ecological perspective. The groundwater heat pump (GWHP) system utilizes groundwater as alternative renewable and clean energy source for space heating and/or cooling, withdraws water from a production well, passes it through a heat exchanger and discharges the water into an injection well. By utilizing the relatively stable temperature of groundwater, GWHP system can achieve a higher coefficient of performance. Due to the utilization of groundwater stored in the aquifer, the assessment of the hydraulic capacity of the aquifer based on numerical groundwater models is always needed for the optimum design and the efficient performance of GWHP. In this paper, numerical methods of underground heat-water transfer, energy balance method and thermal storage method were presented to calculate the capacity of unit area of shallow groundwater aquifer. The model results indicate that the numerical method, which is based on performance efficiency of GWHP, represents the behaviour of groundwater pumping/recharging processes, and serves better than energy balance method and thermal storage method, in addition it has been proven itself that this method has the advantages of energy saving and environmental protection. The calculated capacity is positively related to aquifer thickness. It is found that it is easy for ground water recharge in alluvial and pluvial fan located at the piedmont, while the calculated capacity is relatively smaller compared with that of south-east plain where it is not easy for groundwater recharge. [Copyright &y& Elsevier]

Abstract: A reliable supply of energy is essential to maintain and to improve human being''s living conditions. Compared to the conventional coal-fired approach, renewable energy (RE) helps to mitigate the impacts of greenhouse gas emissions to a large extent. As a newly developed sector with large resource potential and good commercial prospects, China''s wind power industry is exceeding expectations. By 2008, installed capacity of wind power in China totaled over 12GW, making China the fourth largest wind market in the world. However, China has to admit the gap with foreign leading countries, mainly in technical R&D for large-scale wind turbine generation units. This paper attempts to formulate an analytical model for studying and assessing factors that have significant impacts on the local industry. An improved dynamic Diamond Model is developed to help the international community to understand the status quo of the Chinese wind power industry. In order to build a stronger wind power industry, the elements identified in the model need to be strengthened. [Copyright &y& Elsevier]

Abstract: Wind power in China registered a record level of expansion recently, and has doubled its total capacity every year since 2004. Many experts believe that China will be central to the future of the global wind energy market. Consequently, the growth pattern of wind power in China may be crucial to the further development of the global wind market. This paper firstly presented an overview of wind energy potential in China and reviewed the national wind power development course in detail. Based on the installed wind capacity in China over the past 18 years and the technical potential of wind energy resources, the growth pattern was modeled in this study for the purpose of prospect analysis, in order to obtain projections concerning the development potential. The future perspectives of wind energy development in China are predicted and analyzed. This study provides a comprehensive overview of the current status of wind power in China and some insights into the prospects of China''s wind power market, which is emerging as a new superpower in the global wind industry. [Copyright &y& Elsevier]