Thermal Power Generation

Construction and Operation Technology of Thermal Power Plants (Gas)

Proper maintenance, updating, and modification of gas-fired power stations have improved thermal efficiency and enabled stable operation.

  • Yanai power station (Yamaguchi Prefecture, 1,400 MW of total output) is a combined-cycle gas turbine (CCGT) power plant in which the gas turbine is combined with a steam turbine. The gas turbine system was updated, and thermal efficiency was improved in the Unit 1 system.
  • Currently operating systems of Mizushima power station and Tamashima power station (Okayama Prefecture) were modified (use of gasification and multi-fuel systems) to improve supply stability, environmental performance, and fuel cost efficiency. For example, the fuel conversion of Unit 1 in Mizushima (from coal to CCGT) reduced cost and improved efficiency to suit operating conditions at the power station by continuously using already installed steam turbines, which was enabled by high engineering technologies.

Yanai Power StationGas turbine updating work

Yanai Power Station

Updating to a gas turbine with higher efficiency than conventional systems when updating aged facilities

Mizushima Power StationConversion of fuel

Mizushima Power Station

Fuel conversion work to use LNG in power stations that were using coal and heavy oil as fuels

Tamashima Power StationMultiple fuel system (dual operation)

Tamashima Power Station

Modification of Unit 1 to selectively using LNG for combustion in addition to coal in conventional combustion

Construction and Operation Technology of Thermal Power Plants (Coal)

Chugoku EPCO is increasing capacity, improving efficiency, and reinforcing the environmental performance of coal-fired power stations and applying its expertise to overseas IPP projects.

  • Unit 1 of Misumi power station (Shimane Prefecture, 1,000 MW) that started operation in 1998 is one of the largest coal-fired power stations in Japan. This is the first power station in Japan that applied 600℃-level ultra-supercritical (USC) pressure. Also, utilizing the knowledge gained at the Unit 1, it is under construction for Unit 2 (1,000 MW ) to start operation in 2022. Shin Onoda power station (Yamaguchi Prefecture, 500 MW*2 units of output) started operation in 1986 and 1987 and applied supercritical (SC) pressure.
  • Both power stations provide a stable power supply while maintaining a high level of thermal efficiency for the long term thanks to proper operation and maintenance. (Annual operation rate : approximately 90% or more)
  • In terms of improving environmental performance, Chugoku EPCO has installed environmental facilities to satisfy public demand as required in different eras.

    (Ex: The world's first selective catalytic reduction (SCR) system and a moving electrode type electric precipitator in coal-fired power stations and flue gas desulfurization (FGD) system in coal-fired power stations for the first time among ten power companies in Japan.)

  • In recent years, we are also working on the co-firing of woody biomass by effectively utilizing local forest resources and through alliances with other businesses.

Misumi Power Station

Misumi Power Station

Hofu Biomass-Co-firing Power Station

Hofu Biomass-Co-firing Power Station


Further Development of Clean Coal Technology

  • Chugoku EPCO and the Electric Power Development Company established Osaki Coolgen and is now constructing and operating an experimental plant as a experimental project of integrated coal gasification fuel cell combined cycle of the New Energy and Industrial Technology Development Organization (NEDO).
  • The demonstration test is up to the third steps. The first step (an oxygen-blown IGCC) is completed in February 2019, and we are preparing for the second step (CO2 separation and recovery from the Gas) and third step (IGFC).
  • The final achievement of this project is to realize the integrated coal gasification fuel cell combined cycle (IGFC) in which a CO2 separation and recovery system and fuel cells are combined.

Outline of the Verification Testing System

Outline of the Verification Testing System

Osaki Coolgen

Osaki Coolgen