Taking a 2×1 000 MW unit in northern China as an example

the basic configuration parameters of the natural ventilation direct air cooling system and the surface condensing indirect air cooling system are given

and the technical and economic comparison of the two air cooling systems is made.The results show that:in the technically

the natural ventilation direct air cooling system has a lower operating back pressure when the temperature is high.In the economically

the initial investment of natural ventilation direct air cooling is high

but the annual operating cost (including coal consumption) is low

and it has a good payback period.Finally

combined with the characteristics of natural ventilation direct air cooling system and the winter operation experience of the operation units

the effective measures for antifreeze and reducing the subcooling degree of condensate of natural ventilation direct air cooling system are given.