The early April proclamations from Trump are part of a broad attempt at strengthening coal generation, despite federal data showing its decline.
Tighter standards on coal combustion made by the Biden administration were burdensome, Trump wrote, making the industry less viable.
"Coal-fired electricity generation is essential to ensuring that our nation's grid is reliable and that electricity is affordable for the American people, and to promoting our nation's energy security," the statement reads.
Power companies were required to write a letter to the EPA asking for the extension. A list of the selected units was later published by the administration.
Oklahoma Gas & Electric owns four of the coal-fired units, located in northern and eastern parts of the state. In southeastern Oklahoma, Hugo Generation Station is owned by Western Farmers Electric Cooperative.
Both companies generate energy from several sources, including natural gas and renewables. OG&E's coal units make up about 30% of its generation, while Western Farmers' makes up about 11%.
Matt Caves, vice president of legal and regulatory compliance for Western Farmers, said the company asked for the extension to ensure reliability and save costs for making compliance upgrades.
"Obviously, there's been a national policy transition away from coal," he said. "However, you have to have other generation to replace them."
Caves said the company's board of directors is looking at all options for its coal-fired power plant, including its potential retirement. But the group hopes to keep it running, he said.
OG&E declined StateImpact's request for comment.
The compliance extension is in response to the updated Mercury and Air Toxics Standards, meant to reduce air and water pollution by about 70%. The rule was finalized under the Clean Air Act in 2024.
"By developing these standards in a clear, transparent, inclusive manner, EPA is cutting pollution while ensuring that power companies can make smart investments and continue to deliver reliable electricity for all Americans," Michael Regan, former EPA administrator, said at the time.
Coal generation today makes up a small fraction of the state's production, according to the Energy Information Administration. A 2024 report showed coal is winding down nationwide as renewable sources and natural gas become more available, including in Oklahoma.
In response to the measures taken by Trump to support the coal industry, Oklahoma's Sierra Club said the delay in reducing emissions will continue impacting the state's health and environment. Studies show exposure to coal pollution is linked to respiratory and cardiovascular disease, among other ailments.
"Instead of focusing on making energy cleaner and more affordable for families, President Trump's proposal would subsidize out of date technologies with corporate handouts," said chapter director Kara-Joy McKee.
At least two coal-fired units in Oklahoma are set to retire in the coming years. The Northeastern Plant, operated by the Public Service Company of Oklahoma, is set to close in 2026. The company confirmed in early April it still plans to retire the units.
The Grand River Dam Authority announced in 2023 it planned to replace its last coal plant with a natural gas-fired combustion turbine and generator, as reported by The Frontier. The utility did not respond to a request for comment.
