Re: Time period for power plants to cool down after shut-down

Gas plants also have a 75 F./hr cool down based on turbine metal
temps. Additionally, units with steam drums have a differential
temperature between the inside and outside of the drum to watch out
for (100 F differentials). Forced cooling is about 24 hours as well.

The HRSG on a CCGT is the same as any steam plant since the metals are
the same mostly, it has a drum (or several) and a turbine. Since they
often run at lower pressures, cooling may be quicker.

A simple-cycle GT can bee cooled in about 2 hours for maintance.

David
.