ارزیابی چرخه عمر یک سیستم ترکیبی حرارتی و برودتی خورشیدی و سیستم قدرت در استراتژی عملیات های مختلف

A novel solar building cooling heating and power (BCHP) system driven by solar energy and natural gas is proposed in this paper. The performance of the presented system is greatly dependent upon the operation strategy. The primary energy consumption (PEC) and pollutant emissions of the solar BCHP system in following the electricity loads (FEL) and following the thermal loads (FTL) operation strategies are estimated based on life cycle assessment (LCA). Furthermore, three most important energy-related environment problems and human health issues, global warming, acid precipitation and respiratory effects, are considered to assess the environmental impacts of the system. In order to evaluate the comprehensive benefits achieved by the solar BCHP system in different operation modes, grey relation theory is employed to integrate the energetic benefits with environmental performances. Finally, a numerical case of the solar BCHP system for a commercial office building in Beijing, China is applied to compare the integrated performance in the FEL operation strategy with that of the FTL operation strategy. The results indicate that the energy saving and pollutant emissions reduction potentials of the FTL operation mode are the better than that of the FEL mode.

In many countries, building energy consumption accounts for nearly 40% of the total energy use, and about 40% of greenhouse gas and other air pollutant emissions [1] and [2]. In China, building energy consumption has been increasing at more than 10% a year during the past 20 years [3]. The increasing building energy consumption has lead to more and more building-related problems and environmental impacts. One of mitigation methods is to recover the waste heat in buildings so as to improve the energy efficiency. Because of its energy-efficient technology and friendly environment benefits, combined cooling heating and power system is broadly identified as a friendly alternative for the world to meet and solve energy-related problems and environmental issues [4], [5], [6], [7], [8], [9], [10], [11] and [12]. When combined cooling heating and power system is used for a building, it is called building cooling heating and power (BCHP) system.

LCA integrated with the grey relation theory is employed to estimate the pollutant emissions and PEC of a novel solar BCHP system in FEL and FTL operation strategies. Global warming potential, acidification potential, respiratory effects potential and primary energy consumption are employed as evaluation criteria to assess the energetic and environment performances of the system for a commercial office building in Beijing, China. The evaluation analysis leads to the following conclusions: The optimal solar ratio θ is helpful to maximize the energy saving potential of the system. The optimum solar photovoltaic capacity of the FTL operation mode is larger than that of the FEL mode. According to the energy consumption structure in the operation phase, the PEC of the FTL operation mode is less than that of the FEL mode. While, the fossil energy consumption of the FEL operation mode is lower than that of the FTL mode, thus the environmental issues caused by the FEL operation strategy are less serious than the FTL mode.