An enhanced solar–coal hybrid power generation system by integrating photovoltaic–powered coal pre–drying

To address the issues of high cost and low efficiency in conventional solar–coal hybrid power generation (SCHPG), an enhanced SCHPG by integrating photovoltaic–powered coal pre–drying (PPCP) is developed. This approach utilizes affordable photovoltaic modules in place of trough solar collectors. Small amount of photovoltaics is integrated to drive steam compressor, amplifying it into a significant amount of thermal energy for drying steam cooperating with waste steam recovery. In a standard 660 MW power plant, the innovative SCHPG enhances electric power output by 25.50 MWe and thermal efficiency by 1.76%, respectively. These improvements are 14.5 times of those of the conventional SCHPG. The new SCHPG achieves a 0.083 CNY/kWh of cost of solar–generated electricity, only 5.9% of the conventional SCHPG. By utilizing the distinctive solar conversion mechanism of the new SCHPG, dried coal storage is implemented to mitigate solar energy fluctuations. The new SCHPG exhibits a novel solar conversion mode. Solar energy is first amplified based on solar–driven waste steam recovery, then converted into heating value of fuel using coal pre–drying technique. The superior thermal and economic outcomes demonstrate that the PPCP in new SCHPG holds significant promise for addressing the core issues of conventional SCHPG.