With heat balance method

energy analysis was performed for the thermal system of a 660 MW unit

which showed that the main heat loss of the thermal system lied in the condenser

accounting for 47.1% of the heat input of the fuel

and the fuel utilization efficiency was only 40.1%.So the recovery and utilization of waste heat of circulating cooling water can greatly improve the energy efficiency of the power plant.The low-temperature circulating cooling water technology and water source heat pump heating technology were adopted to recover the exhaust steam condensation heat and eliminate the condenser cold source loss.On this basis

the heat balance and exergy balance method were applied to analyze the energy utilization.The result indicated that the unit fuel utilization efficient was 87.2%

the power generation decreased by 31 MW

and the system exergy efficiency was 53.9% when the low-temperature circulating cooling water heating technology was adopted.The fuel utilization efficient was 87.1%

the power generation increased by 23 MW

and the system exergy efficiency was 42.6% when the water source heat pump heating technology was applied.