Search

This study aims to present a thermodynamic performance analysis and to optimize the configurations of a hybrid combined cooling, heating and power (CCHP) system incorporating solar energy and natural gas. A basic natural gas CCHP system containing a power generation unit, a heat recovery system, an absorption cooling system and a storage tank is integrated with solar photovoltaic (PV) panels and/or a heat collector. Based on thermodynamic modeling, the thermodynamic performance, including energy and exergy efficiencies, under variable work conditions, such as electric load factor, solar irradiance and installation ratio, of the solar PV panels and heat collector is investigated and analyzed. The results of the energy supply side analysis indicate that the integration of solar PV into the CCHP system more efficiently improves the exergy efficiency, whereas the integration of a solar heat collector improves the energy efficiency. To match the building loads, the optimization method combined with the operation strategy is employed to optimize the system configurations to maximize the integrated benefits of energy and economic costs. The optimization results of demand–supply matching demonstrate that the integration of a solar heat collector achieves a better integrated performance than the solar PV integration in the specific case study. [ABSTRACT FROM AUTHOR]

Energy storage is an effective method to match the incompatibility of the ratio of heat to electricity between a combined cooling heating and power (CCHP) system and its users. This paper proposes an internal combustion engine CCHP system integrated with two types of thermal energy storage, which are accorded with energy levels of the waste heats of jacket hot water and exhausted gas after power generation. Correspondingly, two types of storage technologies including a hot water tank and a molten salt tank are introduced into the CCHP system. Then, the thermodynamic models are constructed, and two operation strategies are established to coordinate the operation of the thermal energy storage tanks. Through a case study, their performances are compared from three aspects: primary energy ratio, adjustable area of ratio of heating/cooling to electricity and application in different building loads. The results in summer work condition indicate that the CCHP system integrated with the jacket water storage tank achieves a primary energy ratio of 83.8% and a ratio of cooling to electricity of 2.24, which are both better than the integration of exhausted gas storage tank. These characteristics show that the CCHP system with thermal energy storage tank is more suitable to adopt the operation strategy in which the exhausted gas is adopted to drive the absorption chiller/heater, while the jacket water is used to store heat when the waste heat is larger than the heat demand. [ABSTRACT FROM AUTHOR]