摘要
•Geothermal energy is used to preheat the feedwater in a coal-fired power unit.•The performance of a hybrid geothermal–fossil power generation system is analyzed.•Models for both parallel and serial geothermal preheating schemes are presented.•Effects of geothermal source temperatures, distances and heat losses are analyzed.•Power increase of the hybrid system over an ORC and tipping distance are discussed.