The Anegasaki thermal power station in Japan is being upgraded with three new gas-fired combined-cycle units. Image courtesy of ykanazawa1999.
Three M701JAC gas turbines from MHPS will be used for the Anegasaki thermal power station. Image courtesy of Mitsubishi Hitachi Power Systems.
The Anegasaki thermal power station is owned and operated by JERA. Image courtesy of Ketsudan.

The Anegasaki thermal power station upgrade involves the replacement of four ageing oil and gas-fired units at the facility with three new gas-fired combined-cycle units for a total capacity of 1.95GW.

Located in Chiba Prefecture, Japan, the Anegasaki gas-fired steam power plant has been operational since 1967. The 3.6GW power plant was previously owned and operated by Tokyo Electric Power (TEPCO).

Japan’s Energy for New Era (JERA), which is a 50:50 joint venture between TEPCO and Chubu Electric Power and the world’s biggest LNG buyer, became the owner and operator of the Anegasaki facility by taking over the power plants owned by both the shareholders in April 2019.

A full turnkey contract for the construction of new units at the Anegasaki power station was awarded in March 2020.

Scheduled for commissioning in 2023, the three new combined-cycle units are intended to enhance efficiency as well as reduce environmental emissions of the power station.

Location and site details 

The Anegasaki thermal power station is located on a 930,000m2-site at Anesaki-Kaigan near the Ichihara City, in the Chiba Prefecture of Japan.

The Anegasaki replacement project background

JERA announced the replacement plan for the Anegasaki power station in September 2016. The final environmental impact statement (EIS) for the 1.95GW replacement project was submitted in May 2019. The EIS was acknowledged by Japan’s Ministry of Economy, Trade, and Industry (METI) in June 2019. 

Anegasaki combined-cycle facility make-up 

The three new combined-cycle units at Anegasaki thermal power station will be of 650MW capacity each.

Each new unit will be equipped with a forced air-cooled M701JAC gas turbine, a steam turbine and a heat recovery steam generator (HRSG) from Mitsubishi Hitachi Power Systems (MHPS).

The 1,650℃ class gas turbine unit comes with a 15-stage air-cooled combustor, a four-stage 3,000rpm turbine with advanced blade cooling technologies including extra-thick film thermal insulation coating. It offers greater operational efficiency compared to conventional steam cooling methods.

Designed to operate at 50Hz frequency, the M701JAC gas turbine offers 448MW net output with a ramp-up rate of 53MW/min in simple cycle operation. It measures 16.7m-long, 6.5m-wide, and 6.9m-high, and offers 64% plant efficiency in one-on-one combined-cycle configuration. 

Contractors involved with the Anegasaki power station upgrade 

Mitsubishi Hitachi Power Systems (MHPS) was awarded the turnkey engineering, procurement and construction (EPC) contract for the three new combined-cycle units at the Anegasaki power station in March 2020.

MHPS will manufacture the three gas turbines along with auxiliary equipment at its Takasago Works facility in Hyogo Prefecture, while the three steam turbines will be manufactured at its Hitachi Works in Ibaraki Prefecture. The heat recovery steam generators (HRSGs) and exhaust gas denitriser systems will be sourced from its Kure Works facility in the Hiroshima Prefecture.

Anegasaki thermal power station  

The existing Anegasaki thermal power station comprises six LNG and LPG-fired steam power units commissioned between 1967 and 1979. The rated capacity of each unit is 600MW, while the thermal efficiency of each unit ranges between 42.7% and 43%.

Units one and two of the facility operating on LNG were commissioned in December 1967 and November 1979 respectively. The steam power units also used heavy oil and crude oil as fuel earlier.

Units three and four that previously ran on heavy oil and crude oil were commissioned in June 1971 and September 1972. The units currently use LPG and LNG as fuel for steam-based power generation.

Units five and six, commissioned in April 1977 and October 1979, also use LPG and LNG as fuel.

The existing units are fitted with low NOX burners and exhaust gas denitration equipment for emissions control.

The LNG supply for the power station is sourced from the nearby Futtsu and Sodegaura LNG import terminals.

Infrastructure facilities

The other infrastructure facilities at the power station include three central control rooms, multiple propane and butane tanks, a seawater intake facility, a wastewater treatment facility, and a 275kV switchyard for power evacuation into the grid.