Chimney energy control in combined cycle power plants.

摘要

A combined cycle power plant and a method of operating a combined power plant that performs chimney energy control are provided. The combined cycle power plant includes a gas turbine, an exhaust heat recovery boiler including a plurality of heating surfaces, and a steam turbine. Each heating surface can be partially bypassed during power plant startup to reduce steam generation in the exhaust heat recovery boiler. Energy extracted from the exhaust gas of the gas turbine can be reduced. More energy can be released through the exhaust chimney. The steam turbine can be started without gas turbine load limitations during power plant startup. During power plant startup, the steam turbine can be started while maintaining the high load of the gas turbine without increasing the size of the air-cooled condenser.