Several Senate Democrats on Friday launched an investigation into Meta, OpenAI, xAI, and six other companies over their use of gas to power data centers for artificial intelligence.
The probe — led by Sens. Sheldon Whitehouse (R.I.), Martin Heinrich (N.M.), and Chris Van Hollen (Md.) — seeks information about 12 planned gas projects, including why companies didn’t opt for cleaner sources of power, the impact on local air pollution and greenhouse gas emissions, and any efforts to abate them.
“Gas turbines are not the only option for data center developers looking to meet booming demand,” the senators said in a statement. “Some hyperscale projects have invested in renewables, including solar, wind, and zero-carbon nuclear energy. Others employ battery storage. Gas projects can employ carbon capture to limit their footprints.”
This comes as the AI race has driven a wave of investment in new gas projects by utilities and hyperscalers, who are in some cases building behind-the-meter in order to sidestep lengthy wait times to hook up to the grid. Gas is dispatchable, and therefore in high demand by AI data centers that need constant uptime. A single gigawatt-scale data center can use as much as a midsize city.
In 2025, about 252 gigawatts of gas power was in development in the U.S. — nearly triple that of the previous year, according to research by Global Energy Monitor. A third of that is set to be situated on site at data centers.
The trend has fueled alarm about both public health and the climate crisis, given that burning gas emits toxic air pollutants like nitrogen oxide, carbon monoxide, and particulate matter, along with planet-warming methane and carbon dioxide.
The Colossus AI data center campus in Memphis, Tenn., owned by Elon Musk’s xAI, exemplifies the risks. The site has operated since 2024 with both power from a local utility and dozens of gas turbines. On Tuesday, the company got permission from state environmental regulators to install 41 more turbines, despite complaints that it is flouting air pollution limits.
“Alarmingly, the permit likely underestimates the amount of pollution coming from the site and it fails to show that xAI’s 41 turbines will not cause dangerous levels of air pollution,” the Southern Environmental Law Center said in a statement. (The center has threatened to sue xAI over a separate group of 27 gas turbines installed across state lines in Mississippi to power the Colossus campus, accusing the company of illegally operating them without air permits.)
Senate Democrats, in their letter to Musk, asked whether he considered measures to capture or offset emissions from gas generation or invest in renewable energy and storage, and whether the Colossus project would fail financially if it adopted pollution controls. Senators also asked Musk to specify the type of gas equipment xAI is using.
Similar letters were sent to Meta, OpenAI, Fermi America, American Intelligence & Power Corporation, Joule, Crusoe, and Fundamental Data.
The senators asked Meta about two projects in Ohio and Texas. In New Albany, Ohio, the tech giant is investing $1.6 billion in a 400-megawatt, behind-the-meter gas plant to power AI data centers. In El Paso, a local utility is seeking approval to build a 366 MW gas plant to support Meta’s future data centers, El Paso Matters reported, with Meta expected to cover the costs.
Meanwhile, Fermi — a startup backed by former energy secretary Rick Perry — said it plans to build the country’s largest combined-cycle gas projects at an AI data center campus in Texas. And OpenAI, as part of its Project Stargate with Oracle and Softbank, is investing in gas generation for proposed campuses in New Mexico, Ohio, and Texas.
Crusoe was the lead developer of Project Stargate’s first AI data center in Abilene, Texas. However, the senators asked Crusoe about a separate project in Wyoming. Crusoe in July announced a deal with Tallgrass Energy to build a 1.8-GW campus in the state, with the potential to expand to 10 GW. The companies said it will leverage “multiple energy sources fueled by natural gas and future renewable energy developments in the region.”
The Big Four hyperscalers, including Meta, are the largest corporate buyers of clean energy, including solar, wind, and batteries, according to research by BloombergNEF and the Business Council for Sustainable Energy. They also are investing in newer baseload power technologies like advanced geothermal, small modular nuclear reactors, and long-duration energy storage in hopes they can eventually power AI data centers. Meta in 2025 became the leader, signing more than 10 GW of deals. However, it isn’t enough to match the power demands of their AI data centers, hence the parallel growth in fossil fuel investments.
Senators asked companies to respond to their questions by March 27.
