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This paper presents the investigation of a novel mini channel PV/T and thermal collectors combined heat pump system, using both experimental and theoretical methods. Data were produced under conditions typical for winter days in Lvliang, China. A simulation model is developed to conduct theoretical evaluation based on real-world conditions. The experimental and simulated electrical and thermal efficiency of PV/T panels, thermal efficiency of thermal collectors and COP of heat pump are compared. It is shown that the experimental and simulated results are in close agreement. The errors range from 4.0% to 9.1%, giving us confidence that this model is reasonable to predict the seasonal performance of the system. The experimental and simulated results of the system provide fundamental data for performance analysis in winter conditions and inform further improvements of similar systems in the future. • A novel solar assisted indirect-expansion heat pump system is constructed. • A unified computer model based on this system is developed. • Comparison between the experimental and simulated results are analyzed. • The simulation model is verified which can predict the annual performance. [ABSTRACT FROM AUTHOR]

Abstract Hot dry rock geothermal energy is a type of renewable energy with great development prospects in deep strata. However, it is quite difficult to construct an artificial reservoir. In this paper, deep large-dip-angle fault zone in the Yangbajing geothermal field in Tibet of China is used as a natural artificial reservoir, and a set of hot dry rock heat extraction schemes for such fault modes is proposed. A three-dimensional thermo-hydro-mechanical coupling model is established for the scheme to study the distributions of temperature, stress and seepage during the process of mining fault-mode hot dry rock geothermal energy. The temperature of #1 production well remains 445 °C after 22-year operation and it decreases from 445 °C to less than 200 °C after 15-year operation in #2 production well. The initial vertical stress near the injection well is 199 MPa, which decreases to 193 MPa after 1 year and remains unchanged. The specific water flow in the fault zone between the wells increases negatively and exponentially with the extraction time. The seepage resistance of the fault rock mass gradually decreases. The total effective heat production is 13130 MWa after 22-year operation. Highlights • Fault zone can be used to easily construct artificial reservoir in EGS. • Seepage resistance of fault rock mass gradually decreases with mining time. • Extracted water temperature exponentially decreases with mining time. • A geothermal power plant with capacity of 500 MW has more than 25-year lifespan. [ABSTRACT FROM AUTHOR]

The renewable energy power generation (REPG) in China has experienced tremendous growth in the last decade. To understand this rapid growth, it is necessary to explore how Chinese government triggers the remarkable development of the industry. This paper offers a systematic analysis of the incentive policy system for REPG in China, covering wind power, solar photovoltaic, small hydropower (single-unit power generation capacity less than 50 MW), biomass power and geothermal power. The incentive system contains laws, regulations, policies and industrial plans issued during the 11th and 12th “Five-year Plan” periods (2006–2015). Four major incentive strategies of the Chinese government are identified: research and development incentives, fiscal and tax incentives, grid-connection and tariff incentives, and market development incentives. The results show these incentive methods have played a significant role in promoting the development of REPG in China, but still there are some problems associated with them. International comparisons of the incentive policies with those of Denmark, Germany and US, as well as the strategies to further improve the Chinese incentive approaches are discussed. This comprehensive analysis of China's incentive policy system for REPG helps to understand China's experience in promoting renewable energy, contributing to better decision-making in policy. [ABSTRACT FROM AUTHOR]

Abstract: This paper develops an overall methodology for investigating the thermal and power behaviors of semi-transparent single-glazed photovoltaic window for office buildings in Hong Kong. In order to estimate its overall energy performance, this study is conducted in terms of total heat gain, output power and daylight illuminance. Three simulation models are established, including one-dimensional transient heat transfer model, power generation model and indoor daylight illuminance model. A typical office room reference is chosen as case study, and the weather data from 2003 to 2007 from the Hong Kong Observatory are used as the simulation inputs. By incorporating the simulation results, the overall energy performance can be evaluated in terms of electricity benefits corresponding to five orientations of the studied typical office. The priority of office orientation considering overall energy performance is: south-east, south, east, south-west and west. The findings show that thermal performance is the primary consideration of energy saving in the entire system whereas electricity consumption of artificial lighting is the secondary one. The overall annual electricity benefits are about 900 kWh and 1300 kWh for water-cooled and air-cooled air-conditioning systems respectively. The application of semi-transparent PV glazed window can not only produce clean energy, but also reduce building energy use by reducing the cooling load and electrical lighting requirements, which definitely benefits our environmental and economic aspects. [Copyright &y& Elsevier]