Analysis of Energy and Exergy of a Two-Circuit Solar Installation with Thermosiphon Circulation

In this paper, a new system is proposed to improve the thermodynamic and economic indicators of solar room heating. The heat pump is integrated with a conventional solar heating system, in which the temperature of the collected heat is reduced by 20 °C to 30 °C to increase the efficiency of solar energy collection. The low-temperature heat collected by the solar collector is increased using a heat pump to generate high-temperature heat for indoor heating in winter and low-pressure process steam for industrial use in other seasons. The results show that the efficiency of the solar collector has increased by 30.50%, its annual effective operating time has reached 2000 hours, which is about four times more than that of a conventional solar heating system. In addition, the parameters of the solar collector area, the volume of the storage tank and the power of the heat pump have been optimized. This work provides a new way to use solar energy more efficiently and economically. Energy analysis shows that with the new flat solar collectors, the average annual values were 2.5 kW, and also high, the COP system in November was 4%.