Life cycle assessment of a solar combined cooling heating and power system in different operation strategies You-Yin Jing a , He Bai a,⇑ , Jiang-Jiang Wang a , Lei Liu b a School of Energy and Power Engineering, North China Electric Power University, Baoding, Hebei Province 071003, China b China Railway Electrification Survey Design & Research Institute CO. Ltd., Tianjin 300250, China article info Article history: Received 3 June 2011 Received in revised form 5 August 2011 Accepted 24 August 2011 Available online 22 September 2011 Keywords: Solar building cooling heating and power system Operation strategy Life cycle assessment (LCA) Energy consumption Pollutant emissions abstract 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 fol- lowing 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 consid- ered 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 inte- grate 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 perfor- mance 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. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction 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 [1,2]. 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 environmen- tal impacts. One of mitigation methods is to recover the waste heat in buildings so as to improve the energy efficiency. Because of its en- ergy-efficient technology and friendly environment benefits, com- bined 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 [4–12]. When combined cool- ing heating and power system is used for a building, it is called building cooling heating and power (BCHP) system. As a kind of renewable energy, solar energy has been applied to BCHP systems to decrease the utilization of non-renewable energy and reduce pollutant emissions. Meng et al. showed that the BCHP system integrated with solar collectors is superior to the traditional BCHP systems concerning the fuel energy saving ratio, equivalent thermodynamic coefficient and exergy efficiency [13]. Medrano et al. calculated the energy cost savings and CO 2 emission reduc- tions of a BCHP system with solar support in comparison to conven- tional energy systems [14]. Wang et al. analyzed the system exergy efficiency variations of a BCHP system driven by solar energy with different slope angle and hour angle [15]. Eman et al. studied the percentage external energy supplied by the solar collectors of a solar-assisted trigeneration system under different levels of carbon credits [16]. The performance of BCHP systems is obviously dependent upon the operation strategy which determines the power and thermal outputs. In general, two simple operation strategies are following the electric load (FEL) and following the thermal load (FTL) [17]. Currently some researchers have studied and compared the energetic and environmental performances of BCHP systems in the different operation modes [18–20]. The energy and environ- ment analysis are very important to the feasibility of BCHP system. Several researchers have evaluated and analyzed the benefits of BCHP systems in terms of energy saving potential and environment impacts with different evaluation methods. Fumo et al. compared the primary energy consumption (PEC) saving and CO 2 emission reduction of a BCHP system based on emission strategy with that of the primary energy strategy [21]. Li et al. established a mix- integer nonlinear programming model to analyze energy demands of BCHP systems for hotel and hospital [22]. Wang et al. studied the energetic and environmental benefits achieved by BCHP systems in comparison to separate production system based on a particle swarm optimization algorithm [23]. 0306-2619/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.apenergy.2011.08.046 ⇑ Corresponding author. Tel.: +86 312 7522443; fax: +86 312 7522440. E-mail address: kulapikaleio@163.com (H. Bai). Applied Energy 92 (2012) 843–853 Contents lists available at SciVerse ScienceDirect Applied Energy journal homepage: www.elsevier.com/locate/apenergy