基于光伏驱动余热回收的新型太阳能-燃煤混合发电系统热力学与经济性分析

Abstract Developing solar–coal hybrid power generation system (SCHPGS) enables low–carbon and stable electricity generation. To address the key challenges of high cost and unsatisfied solar–to–electricity efficiency (SEE) in conventional SCHPGS, a new method was developed: photovoltaic–driven waste heat recovery . The connection between photovoltaics and thermodynamic cycles was revealed, and a novel SCHPGS was proposed. In the proposed system, photovoltaic modules were employed instead of high–cost trough solar collectors. The photovoltaic power was used to drive a compression heat pump (CHP), achieving amplified solar utilization by waste heat recovery. The low–grade thermal energy produced by the CHP was effectively integrated into air preheating for energy cascade utilization. Thermodynamic and economic analyses of the proposed SCHPGS were performed. For a 600–MW base plant, the system exhibited a high SEE of 35.28 %, which was 1.6 times that of the conventional SCHPGS. By employing low–cost photovoltaic modules and achieving amplified solar utilization, the proposed SCHPGS delivered a low cost of solar–generated electricity at 0.376 CNY/kWh, only 34.3 % of that of conventional SCHPGS.