Inlet-air cooling system with centrifugal-chiller module.

Mitsubishi Heavy Industries, Ltd. (MHI) has developed an inlet-air cooling system in which large-scale and highly efficient centrifugal-chiller modules are applied to gas turbine combined-cycle (GTCC) power plants. In a gas turbine, the output power decreases as the temperature of inlet air increases. Our new inlet-air cooling system contains a cooling-coil module and a chiller module. In the chiller module, centrifugal chillers, cooling towers, water supply pumps, an electric power unit, a transformer, and a control unit, are packaged as a single unit. An Ene-Conductor “EC series” control unit was adopted as the main controller for the system. This newly developed inlet-air cooling system significantly increased power output of a GTCC power plant. The system is installed at a GTCC plant in Thailand and started commercial operations in 2012.