运用热力学的热平衡和火用分析原理,对几种太阳能热水系统进行了用能效率分析,得出了强制循环太阳能热水系统的热效率和火用效率为最高、自然循环次之、直流式系统最低,分析了太阳能热水系统火用损最大部分是因管路的散热所致,因此加强循环管路绝热保温是提高太阳能热水系统用能效率的主要途径 Based on the thermodynamic equilibrium theory and exergy analysis, the energy efficiency of several solar hot water systems was analyzed. The results showed that the thermal efficiency and exergy efficiency of the forced circulation solar hot water system were the highest, followed by the natural circulation. The direct current system The lowest, the analysis of the solar water heating system, the largest part of the loss due to heat dissipation due to the pipeline, so strengthening the cycle of pipe insulation is to improve the energy efficiency of solar water heating system, the main way