MHI Introduces 50Hz F Class Gas Turbine Upgrade:
M701F5 Gas Turbine Features Combined Cycle Capacity of 520MW and
Enables over 61% Thermal Efficiency in GTCC Applications

The M701F5 design is based on the preceding M701F4 and leverages experience with the MHI F fleet: 182 units in operation around the globe, with more than 7 million actual operating hours and 70,000 starts. The compressor section retains the M701F4's airflow with the mid and rear stage profiles have been modified from NACA1 to CDA2. The combustion system is based on the verified GAC engine, and the turbine section incorporates state-of-the-art gas turbine technologies developed for the J Class, including advanced cooling technology and advanced thermal barrier coatings.

The M701F5 gas turbine achieves a rated simple cycle power output of near 350 MW (ISO basis) and 520 MW in combined-cycle (GTCC) power generation. In GTCC applications, high-temperature exhaust gas from the gas turbine is used to generate power by a steam turbine. MHI is aiming to achieve GTCC thermal efficiency in excess of 61%.

MHI produces gas turbines on a vertically integrated basis, from conceptual and detailed designs to verification and manufacturing, at its Takasago Research & Development Center and Takasago Machinery Works in Takasago, Hyogo Prefecture. MHI operates a verification combined-cycle power plant at the site to validate advanced turbine technology, with capability to test air-cooled as well as steam-cooled engines. The company is currently conducting stringent verification tests on the M501J gas turbine and its core technologies. The results of the J-series validation have provided invaluable data for the M701F5's components, which are derived from the J design.

With GTCC type power generation, gas and steam turbines are used in combination to generate electricity, utilizing high-temperature exhaust gas from the gas turbine. This configuration enables GTCC power plants to achieve higher thermal efficiency than other plants based on earlier technologies, such as conventional boiler steam turbine plants. Higher efficiency results in reduced fuel consumption relative to electricity output and lower CO2 emissions, making GTCC plants friendlier to the environment. GTCC power generation with the M701F5 will achieve CO2 emissions 50% lower than conventional coal-fired power generation (comparison with MHI power plants). In this way, the newly developed turbine is expected to contribute significantly to worldwide efforts to reduce global warming.

Notes:
1.NACA: blade profile as defined by the former National Advisory Committee for Aeronautics (reorganized into the National Aeronautics and Space Administration [NASA] in 1958)
2.CDA: controlled diffusion airfoil