Our History

Khanom Power Plant is the largest power plant in Southern Thailand. The plant is located on an area of 484 rai at the mouth of the Khanom River, Khanom District, Nakhon Si Thammarat. Khanom Power Plant Unit 4 has a power purchase agreement (PPA) with the Electricity Generating Authority of Thailand (EGAT) for 930-megawatts of electricity supply for 25 years.

Khanom Power Plant uses natural gas from the Gulf of Thailand as the main source of fuel. Natural gas is delivered through the 320-kilometer pipeline to the gas separation facility in Khanom and then to the gas metering and regulating station at the north of the power plant. This gas supply system can sustain the required natural gas volume during the power plant’s maximum load of 230 cubic feet per day.

History of Khanom Power Plant Unit 1-3

In the past, the Khanom Power Plant comprised 3 electricity generating units of 2 different types – thermal power plant and combined cycle power plant.

Khanom Thermal Power Plant Unit 1(Khanom Thermal Power Plant Unit 1)

In October 1978, EGAT completed the feasibility study for the Khanom Power Plant Unit 1 and received approval from the Cabinet on March 13, 1979. Construction of the site started in July 1979 while the power plant barge was made in Japan and completed on September 25, 1980. The power plant barge was towed 3,000 nautical miles from Japan to Khanom. The barge arrived in Thailand on October 13, 1980 after an 18-day journey by sea. The installation was completed on October 15, 1980 and the test run began immediately. On February 24, 1981, the power plant began commercial operations and started to distribute electricity with an installed capacity of 75 megawatts.

Today, Khanom Power Plant Unit 1, which is the country’s first and only power plant barge, has been transformed into the Khanom Learning Center where the general public and young people come to learn more about electricity and the electricity generating process.

Khanom Thermal Power Plant Unit 2

Khanom Thermal Power Plant Unit 2 was initiated as a contingency project by EGAT. The plan was proposed as a component of the 6th National Economic and Social Development Plan with the aim of strengthening power security in Southern Thailand. The plan was approved by the Cabinet on July 1, 1986. The power barge and power plant equipment were made in South Korea, with work commencing in June 1987. Once complete, the power plant barge was loaded onto a large ship and transported by sea to Thailand. The installation was completed on October 14, 1988. The construction of the remaining part of the power plant then continued and once completed underwent testing. The power plant, which has an installed capacity of 75 megawatts, started distributing electricity to the transmission system on November 6, 1989.

In 1990, local electricity demand soared. To cope with the upward trend for demand, EGAT proposed the building of the Khanom Combined Cycle Power Plant by including the project in the National Power Development Plan. The project was approved by the National Economic and Social Development Board on May 3, 1991 and by the Cabinet on August 6, 1991.

The Khanom Thermal Power Plant Unit 2 has now been demolished. Equipment and parts have already been relocated in line with Safety, Health, and Environment measures.

Khanom Combined Cycle Power Plant

The Khanom Combined Cycle Power Plant is located in the same area as the Khanom Thermal Power Plant Units 1 and 2. Located on a site of approximately 30.5 rai, the power plant can produce 3,154 kilowatt-hour on average per year. It comprises 5 generators, including 4 gas turbines and 1 steam turbine, with total installed capacity of 674 megawatts.

Gas turbine: The four 112-megawat gas turbines

are mainly powered by natural gas and use diesel oil as a secondary source of energy. Each unit can support a maximum of 33.92 million cubic feet of natural gas. (Where diesel oil is used, 0.835 million liters of oil are required.)

Steam turbine: The 226-megawatt steam turbine

uses heat from the four gas turbines’ emissions to boil water. High-pressure steam will drive the steam turbine to start the generator. The demolition of the steam turbine is currently being undertaken. Machines, equipment and parts are being relocated in line with the Safety, Health, and Environment regulations and measures.

Power Plant Construction Commercial Operation End of Agreement Installed Capacity
Khanom Power Plant Unit 1 2522 (1979) 2524 (1981) 2554 (2011) 75 MW
Khanom Power Plant Unit 2 2529 (1986) 2532 (1989) 2559 (2016) 75 MW
Khanom Power Plant Unit 3 2534 (1991) 2537 (1994) 2559 (2016) 674 MW
Khanom Power Plant Unit 4 2556 (2013) 2559 (2016) 2584 (2041) 970 MW