The US Environmental Protection Agency has issued guidance confirming that power plants built to serve a single data centre, rather than the wider electricity grid, are not covered by one of the Clean Air Act’s oldest pollution-control programmes. The move, reported by Grist, comes as American energy developers scramble to build new gas-fired generation to meet surging demand from artificial intelligence data centres.
What the guidance changes
The Acid Rain Program was added to the Clean Air Act in 1990 to curb sulphur dioxide and nitrogen oxide emissions from large power plants, pollutants linked to smog and acid rain. It requires participating plants to continuously monitor and report their emissions, a requirement known as continuous emissions monitoring, or CEMS. According to industry data cited by LandGate, the programme has cut these emissions from power plants by roughly 90 percent since it began.
The programme has historically applied only to utility plants that sell electricity to the public. In a document dated 16 July 2026 and confirmed publicly on 27 July, the EPA stated that the Acid Rain Program ‘does not apply to power generation facilities that are not connected in any way to the larger electricity grid.’ The agency and several experts argue that islanded plants, those built to power a single site, were never genuinely covered by the rule to begin with, since it applies to generators that sell power or report to the US Department of Energy.
The guidance expands opportunities for companies to develop and operate islanded power generation facilities for data centers.
A boom in dedicated gas plants
The exemption removes one of several federal permits that independent power plants built for data centres would otherwise need. It also aligns with the Trump administration’s ‘Ratepayer Protection Pledge,’ under which companies commit to building or buying all the power their facilities need and covering its full cost, rather than passing expenses on to ordinary electricity customers.
The scale of the projects at stake is significant. Amazon is planning a 7.65-gigawatt gas plant in Texas to serve a data centre, which would rank among the largest power plants of any type in the country. Nexus has proposed a separate 6-gigawatt gas plant in the same state. In Georgia, microgrid developer VoltaGrid has applied to build a 90-megawatt facility to power a Serverfarm data centre, while the EPA’s own guidance cites a 500-megawatt gas plant proposed for an unnamed data centre as an example of the kind of project the new interpretation covers.
If an islanded plant later connects to the public grid, it could become subject to Acid Rain Program requirements after all, according to the guidance. And because the guidance is not a binding rule, state environmental agencies retain the authority to impose stricter permitting conditions than the federal floor. It is these state regulators, not the EPA, who will actually issue permits for the projects.
Concerns over oversight
Environmental groups, including Earthjustice, have urged the EPA not to let data centres and other large polluters begin construction before securing proper permits. Critics say the loss of continuous emissions monitoring removes one of the most reliable ways to verify what these new gas plants are actually emitting, at the exact moment the industry is expanding at unprecedented scale to meet AI-driven electricity demand.
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