Mae Moh power station

From Global Energy Monitor
This article is part of the CoalSwarm coverage of Thailand and coal
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Mae Moh power station (โรงไฟฟ้าแม่เมาะ) is a 2,455-megawatt (MW) coal-fired power station in Mae Moh, Thailand.


The undated satellite photo below shows the plant.

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Background on Plant

In 1953, lignite coal was found at Mae Moh basin, leading to construction of the Mae Moh lignite power plant. Three 75 MW generators were installed from 1978 to 1981, Units 4-7 (150 MW each) were constructed in 1984 and 1985, and Units 8-13 (300 MW each) were built from 1989 to 1995, for a total of 13 generators (2,625 MW). The Electricity Generation Authority of Thailand (Egat) has a license to operate a coal mine in the province to supply fuel to the power plant.

The plant is fueled by the Mae Moh coal mine, an open pit lignite mine which produces 40,000 tons per day. With an area of 135 square kilometers, it is considered the largest coal-fired power plant in Southeast Asia.[1]

On its website the Italian-Thai Development, a major Thai construction company, stated that it worked on Units 8-13 between 1986 and 1992. The website lists its role as relating to the "fabrication and delivery of steel work for gas and air ducts of the boiler buildings, turbine buildings and cooling water system."[2]

A replacement unit for Units 4-7 began operating in August 2019, as detailed below.

In 2019, The Nation Thailand reported that Units 8-9 would retire in 2025, and that Units 10-13 would retire after 2025 as it was estimated that the related coal mine's supply wouldn't be sufficient to feed them.[3]

The Thailand Power Development Plan for 2018-2037, as revised in 2020,[4] appeared to list Unit 8 for discharge in 2022, Units 9-11 for discharge in 2025, the additional replacement unit for Units 8-9 for completion in 2026, and Units 12-13 for discharge in 2026.[5]


Generating Units 1 and 2 were retired on March 1, 2000, while Unit 3 was taken out of service in 1999.[6]

Replacement units

Units 4-7

Units 4 through 7 (150 MW each) of the power station were replaced in 2019.[7][8] As of 2014, Team Consulting Engineering and Management Co., Ltd. was working on the environmental and health impact assessment of the 600 MW coal project.[9]

In March 2015, Alstom and Marubeni Corporation were contracted to provide a 600 MW ultra-supercritical unit at a cost of US$1 billion.[10]

The National Council for Peace and Order approved the Mae Moh Power Plant Units 4-7 Replacement Project on August 19, 2014, and the National Environment Board approved the EHIA Report on December 17, 2014. According to EGAT, construction began on replacement Units 4-7 in April 2015. The unit was planned to be ultra-supercritical. Alstom and Marubeni were the contractors. The commercial operation date was expected in November 2018.[11]

The Thailand Power Development Plan for 2015-2036 forecast that the Units 4-7 replacement would be operational in 2018.[12][13]

The country's draft Power Development Plan for 2018-2037 still listed the Unit 4-7 replacement as planned for commissioning in 2018.[14] However, in April 2019, Egat said it was testing the operation of the Mae Moh Power Plant Units 4-7 Replacement Project, with operation planned for 2019. The unit was described as 655 MW.[15]

The Units 4-7 replacement began operating in August 2019.[8]

Units 8-9

The Thailand Power Development Plan for 2015-2036 noted an additional replacement for Unit 8-9 was planned for completion in 2022.[12][13]

The Units 8-9 replacement was also proposed to be 655 MW.[16] It appeared listed in the Thailand Power Development Plan for 2018-2037 as planned for commissioning in 2026. The plan (PDP2018) was approved by the National Energy Policy Council (NEPC) on January 24, 2019 and by the Cabinet on April 30, 2019. In March 2020, the NEPC approved a revision of Thailand's PDP2018 (PDP2018 Rev.1), among other plans.[17][4]

In July 2019, over 3,000 Mae Moh residents and interest public members participated in the first public hearing for the Units 8-9 Replacement Project.[18][19]

In August 2020, it was reported that the country was facing excess power capacity due to decreasing demand from the covid pandemic. As a result, Ratch chief executive Kijja Sripatthangkura said Egat should delay development of the Units 8-9 replacement at Mae Moh.[20]

Units 8 and 9 have been running on standby mode, and the two power generators related to the units are expected to be decommissioned in 2022.[19]

The Thailand Power Development Plan for 2018-2037, as revised in 2020, noted the additional replacement for Unit 8-9 was planned for completion in 2026. It also appeared to list Unit 8 for discharge in 2022 (at page 2.1-1) and unit 9 for discharge in 2025 (at P 2.1-2).[5]

As of May 2021, the Units 8-9 replacement's Environmental and Health Impact Assessment (EHIA) appears to have been at least partially approved by the National Energy Regulatory Commission (ERC) and National Environment Board (SEC). Another hearing was to be held in mid-2021 by the ERC before adding any additional comments to the report.[21]


According to the Asian Development Bank (ADB), it has been involved in Mae Moh mine for financing several units. It approved a series of loans amounting to more than US$352 million for the past twenty years.[22][23]

Egat was budgeting 37 billion baht (US$1.1 billion) for development cost for the Units 8-9 replacement project.[19]

Environmental and Social Impacts

According to Greenpeace, the Mae Moh power plant approximately contributes more than four million tons of carbon dioxide emission in the atmosphere annually. In addition, around 1.6 million tons of sulfur gas is released from the power plant into the air every day. Greenpeace also said that from the time of the implementation of the Mae Moh coal power plant, more than 30,000 people have been displaced and thousands acquired severe respiratory problems due to the inhalation and exposure to sulfur dioxide emitted from the mine. In October 2003, the State Natural Resources and Environmental Policy and Planning Office found high levels of arsenic, chromium, and manganese in almost all water sources within the vicinity of the plant.[24]

The fly ash has also affected the crops of villagers. According to one villager, her planted vegetables and fruits died because of the toxics that the coal power plant emitted. Another villager recounted that her pineapple plantation wilt over the years. Farmlands have been negatively affected by acid rain which is attributed to the sulfuric dioxide released by the coal power plant. In May 2004, the Thai Provincial court awarded US$142,500 to the villagers for crop damages caused by the coal power plant.[25]

To mitigate the negative impacts of the plant, pollution control devices, such as flue gas desulfurization (FGD) and ionizing wet scrubbers, were installed by the government.[1]

Involuntary Resettlement Policy

Due to the implementation of the project, more than 30,000 people have been displaced. According to reports, Thailand’s cabinet previously offered to build houses for those who were affected. However, there has reportedly been no progress.[1]

Community opposition

In 2003 communities near the power station and lignite mines sued Egat in Administrative Court seeking redress from mining power generation fallouts. In February 2015, the Supreme Administrative Court ordered the Electricity Generation Authority of Thailand to set up a committee to consider evacuating villagers affected by pollution from the lignite mines and Mae Moh power plant out of the five-kilometre radius from the facilities.[26]

Project Details

  • Sponsor: Electricity Generating Authority of Thailand (Egat)
  • Location: Mae Moh sub-district, Mae Moh district, Lampang province
  • Coordinates: 18.296, 99.752 (exact)
  • Status: Retired (Units 1-7); Operating (Units 8-13, Units 4-7 replacement); Pre-permit development (Units 8-9 replacement)
  • Gross Capacity & Start year:
    • Units 1-3 (Retired): 3 x 75 MW (1978-1981)
    • Units 4-7 (Retired): 3 x 500 (1985-1986)
    • Units 8-13: 6 x 300 MW (1989-1995)
    • Units 4-7 replacement: 1 x 655 MW (2019)
    • Units 8-9 replacement: 1 x 655 MW
  • Type: Units 4-7 replacement: Ultra-supercritical; Units 8-9 replacement: unknown
  • Coal Type: Lignite
  • Coal Source: Mae Moh basin 
  • Source of financing:

Articles and resources


  1. 1.0 1.1 1.2 "The Grievous Mae Moh Coal Power Plant," ADB, February 2, 2008.
  2. Italian-Thai Development, "Industrial and power plants," Italian-Thai Development website, accessed May 2011.
  3. "Egat prepares to shut down Mae Moh coal mine in Lampang," The Nation Thailand, October 26, 2019.
  4. 4.0 4.1 Supasit Boonsanong and Charuwan Charoonchitsathian, Tilleke & Gibbins, "Electricity regulation in Thailand: overview," Thomson Reuters, last updated October 1, 2020
  5. 5.0 5.1 "Power Development Plan 2018-2037, revision 1," Energy Policy and Planning Office, October 2020 (appendix, pages 2.1-1 to 2.1-2).
  6. "Mae Moh power plant," EGAT, accessed January 2014.
  7. "Summary of Thailand Power Development Plan 2012-2030, Revision 3," Ministry of Energy, June 2012, Table 4.1.
  8. 8.0 8.1 "Lampang Media Visit Mae Moh Thermal Power Plant, Unit 1,", February 13, 2020.
  9. "Replacement of Units 4 – 7 at Mae Moh Power Plant, Lampang," Team Group, accessed February 2014.
  10. "Alstom to build the first ultra-supercritical lignite-fired power plant in Asia," Alstom, March 9, 2015.
  11. "First piling of Mae Moh Power Plant Units 4-7 Replacement Project, raising the efficiency of power generation together with environmental care," EGAT, May 11, 2015.
  12. 12.0 12.1 "Thailand Power Development Plan, 2015-2036," Thailand Ministry of Energy, May 2015.
  13. 13.0 13.1 "Mae Moh Power Plant," Egat website, accessed December 2016.
  14. "Draft of Power Development Plan 2018-2037," Energy Policy and Planning Office, December 2018 (links to guidelines; does not link to Draft PDP2018).
  15. "EGAT’s Mae Moh Power Plant Units 4-7 Replacement Project proceeds," EGAT, April 1, 2019.
  16. "Egat to propose coal plant upgrade," Bangkok Post, October 2, 2018.
  17. "Power plan backed along with 2 plants," The Nation, January 25, 2019.
  18. "Over 3,000 people attend 1st public hearing for EHIA of Mae Moh Power Plant Replacement Project, Units 8-9," EGAT, July 18, 2019
  19. 19.0 19.1 19.2 "Egat begins public hearings for Mae Moh coal plant units," Bangkok Post, July 13, 2019.
  20. "Egat reining in power reserves," Bangkok Post, August 20, 2020.
  21. "กฟผ. เดินหน้าโรงไฟฟ้าแม่เมาะทดแทนฯ รักษาความมั่นคงตามแผน PDP,", March 28, 2021.
  22. Rosien, Jessica. “ADB’s Dirty Involvement in Coal-Fired Power.” Bankwatch. Vol. III, Is. 2, December 2004.
  23. “Project Performance Audit Report on the Third Power Transmission (Sector) Project (Loan 1170-THA) and Fourth Power Transmission (Sector) Project (Loan 1245-THA) in Thailand,” Manila: Asian Development Bank, September 2002.
  24. “All Emission, No Solution: Energy Hypocrisy and the Asian Development Bank in Southeast Asia,” Greenpeace Briefing, May 2005.
  25. Meesubkwang, Saksit. “More Locals Claim Poisoning by Mae Moh Power Station in Lampang.” Chiang Mai Mail. Vol. V, No. 26, June 24-June 30, 2006.
  26. "Egat ordered to evacuate affected villagers from Mae Moh power plant," Thai PBS, February 10, 2015.

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