Manufacturing and Construction, Operation of Karita PFBC 360 MW Unit

Pressurized Fluidized Bed Combustion Combined Cycle Power Generation, namely, PFBC is the clean coal technology, utilizing gas turbine and steam turbine, which is high efficient and friendly to earth. In early 90’s, 70 MW class PFBCs had started demonstration and commercial operation all over the world. Kyushu Electric Power Company (KyEPCO) decided to apply this technology as the real commercial unit, the world largest capacity 360MW, and put into commercial operation in July 2001. To apply PFBC to the large-scale commercial plant, it is essential to demonstrate the higher efficiency than any other conventional coal firing units. In order to achieve this, the gas turbine with higher operation pressure and advanced supercritical steam condition for steam turbine were applied. The reduction by size and weight of the equipment is the vital must to realize large scale PFBC, as 360MW unit. To reduce the pressure vessel size, the unique design of hexagon furnace was applied to install it efficiently in smaller vessel. The plant has started commercial operation in July 2001 and has well demonstrated PFBC’s technology advantages as planned. It achieved the efficiency, 41.8% as net value based on HHV, which is the highest level among existing coal fired power plants. It also verifies smooth operation, 3%L/min of Load following capability, 3 hours of hot start-up, that is comparable to conventional pulverized coal fired unit.