Monroe Power Co
Owned by Southeast PowerGen LLC
Operated by Cogentrix
380-MW, gas-fired, two-unit, simple-cycle plant located in Monroe, Ga
Plant manager: Mike Spranger
Turbine-enclosure ventilation-system upgrade
Challenge. During a test run following a planned maintenance outage, one unit experienced a fire-system high-temperature trip in the turbine enclosure which caused a turbine trip. One of the contributing factors to the fire-system trip was that the turbine enclosure ventilation system did not respond to the rising temperature fast enough.
Solution. Staff designed and installed upgraded ventilation system controls. The thermostats by the door were replaced by RTDs mounted on the ceiling so that the ventilation system is operating based on the hottest areas in the turbine enclosure. Louvers operate independently from the fans at a lower-temperature setpoint, allowing heat to escape naturally and reduce the stress on fans and motors. A ventilation graphics screen was added to the DCS so a control room operator can monitor and operate the system remotely.
Results. The ventilation upgrade, completed for less than $500 per unit, improves the operation and reliability of the gas turbines.
Project participants: James Goins, Chris Harris, Scott Hobbs, Charles Gibson, Nick Sanz, Bly Crane.