To help achieve the national carbon emission peak and carbon neutrality goal on schedule

upgrading coal-fired units has become an important measure in the field of energy and power in China. A subcritical 600 MW coal-fired power unit in a power plant is taken as the example

aiming at the goal of reform for capacity and efficiency increase

the advanced AIBT flow path retrofit technology and auxiliary energy-saving technology were used to carry out retrofit for the unit. The performance acceptance test of the coal-fired power unit after capacity and efficiency increasing retrofit was carried out

and the thermal economic indicators of the unit before and after retrofit were comparatively analyzed. The results show that

the unit capacity increased from 600 MW to 630 MW

the heat consumption rate of the unit at rated load decreased to 7 726.03 kJ/(kW·h)

which was 500.17 kJ/(kW·h)lower than that before the retrofitting

and was lower than the retrofit target value. The standard coal consumption for power supply was 289.68 g/(kW·h)

which was 7.5% lower than that before the reconstruction. The retrofit case of capacity and efficiency increasing of the subcritical 600 MW unit can provide references for safe energy-saving and upgrading of coal-fired power units.