Update on Mitsubishi G Series Gas Turbines With Over 78,000 Hours Fleet Operation

Seven G gas turbines from Mitsubishi are in commercial operational at various combined cycle power plants since the first Mitsubishi G gas turbine was inroduced in 1997. The combined operating time on the fleet exceeds over 78,000 actual hours. Additional power plants using Mitsubishi G-series gas turbines are in advanced stages of commissioning in the U.S.A., and are expected to be in commercial operation in 2003. This paper describes operating experience of the Mitsubishi G-series gas turbines, which apply steam-cooling instead of air-cooling to cool the combustor liners. The paper discusses design enhancements that were made to the lead M501G gas turbine at Mitsubishi’s in-house combined cycle power plant facility. It also addresses the effectiveness of those enhancements from the standpoint of hot parts durability and reliability at other power plants that are in commercial operation using Mitsubishi G gas turbines.