Old coal plants in the U.S. are being turned into giant AI data centers because they already have the power lines, cooling systems, and good locations needed for fast computers.
Why are former coal plants being converted into AI data centers?
Former coal plants are ideal for AI data centers because they already have grid-ready infrastructure, including high-voltage transmission and water-cooling systems. Repurposing these sites cuts permitting time by 2–3 years, reduces construction costs, and leverages locations close to population centers for lower latency.
The world’s appetite for artificial intelligence is expanding so rapidly that the most convenient places to host the required data centers are former coal plants. Across the United States, decommissioned coal stations are being reopened – not to burn more coal, but to house floors of GPUs and server racks that will train the next generation of AI models.
- Why Coal Plants Are the New Gold Mines for AI*
- Grid-ready infrastructure: every shuttered coal plant already has high-voltage switchyards, transmission towers, and water-cooling intake systems. Re-using these assets can cut permitting time by 2–3 years and shave hundreds of millions from construction budgets.
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Location, location, location: proximity to population centers means lower latency for cloud services and faster fibre back-haul.
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Homer City: from Smokestacks to Silicon
The most visible example is the Homer City Energy Campus* in Indiana County, Pennsylvania:
| Project detail | Stat |
|---|---|
| Total investment | $15 billion |
| Power source | 4.5 GW natural-gas plant (60–65 % lower CO₂/MWh than the original coal units) |
| Construction start | 2025 |
| First servers online | 2027 |
| Permanent jobs | ~1,000 high-skill tech roles |
| Construction-phase jobs | 7,000–10,000 |
According to Data Center Frontier, the campus will be the largest natural-gas-powered AI complex in North America.
- Environmental Impact: Numbers from the Assessment
A July 2025 Pennsylvania Department of Environmental Protection* review shows:
| Parameter | Coal (legacy) | Gas + AI (2027) | Change |
|---|---|---|---|
| CO₂ per MWh | 1,000 kg (est.) | 350–400 kg | -60–65 % |
| SOâ‚‚ | High | Negligible | -95 % |
| Water withdrawal | ~300 MGD | ~160 MGD | -47 % |
| Noise at property line | Variable | <55 dB(A) nights | Meets limits |
While absolute emissions fall, total electricity demand is still rising fast:
| Forecast | Global data-center power growth |
|---|---|
| 2023 | baseline |
| 2030 | +165 % (Goldman Sachs) |
| 2035 | U.S. alone could reach 12 % of national demand |
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Policy Fast-Track
The federal government is greasing the wheels. A July 2025 executive order* explicitly rescinds earlier climate-impact assessments for AI data centers on federal land and offers loan guarantees for gas pipelines and turbines. The result: projects that once waited five years for permits are now measured in months. -
Local Voices*
Residents near Homer City worry about: - Water stress: cooling towers will still need 160 million gallons per day during peak summer.
- Grid strain: voltage fluctuations that could raise household electric bills.
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Noise : nighttime server-farm humming, although modeling shows it will stay within state limits.
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What Comes Next
Developers are already scouting the next batch of ex-coal sites. Internal memos list 17 additional U.S. coal plants* across Ohio, Illinois, and West Virginia undergoing feasibility studies for AI conversion. If all proceed, the combined new load could rival the entire power demand of Belgium by 2032. -
Bottom line*
Every new AI breakthrough pushes electricity demand higher. Re-using coal infrastructure is cheaper and faster than building from scratch, but it also locks in another decade of fossil-fuel generation. Whether the climate math works depends on how quickly carbon-free sources – hydrogen-ready turbines, advanced nuclear, or long-duration batteries – can be swapped in before these gas plants hit mid-life.
Why are old coal plants suddenly turning into AI hubs?
Developers are racing to snap up decommissioned coal sites because they already have three things every data center needs: direct high-voltage grid ties, abundant cooling water, and hundreds of acres of flat, industrially-zoned land.
At Homer City Energy Campus in Pennsylvania, the former 2 GW coal plant will be replaced by a $15 billion natural-gas-powered AI complex that can deliver up to 4.5 GW of electricity – enough to run more than 3 million average U.S. homes at once.
Construction starts in 2025 and the first servers are scheduled to spin up in 2027.
How much cleaner is a gas-powered data center compared with coal?
Switching from coal to combined-cycle natural gas turbines cuts CO₂-equivalent emissions per megawatt-hour by 60–65 %, according to project documents filed with Pennsylvania regulators.
The turbines (GE Vernova 7F.05 units) will also ship hydrogen-ready, meaning up to 20 % hydrogen can be blended into the fuel stream once regional supply is available – an upgrade path that could shave another 7–10 % off the carbon footprint.
Will my electric bill go up?
In regions where new gas-plus-data-center projects add load faster than renewables are built, ratepayers could see increases.
A 2025 analysis by Utility Dive found that 17 U.S. coal and gas plants originally slated for retirement are now staying online to serve data centers, and utilities are passing $8–12 billion in new infrastructure costs to customers.
However, Pennsylvania offers 10-year property-tax abatements and state grants for grid upgrades, which project sponsors claim will limit residential bill impacts to <1 % in the first decade.
What about noise, water use, and local air quality?
- Water: The new plant will withdraw ≈ 70 % less water than the old coal unit thanks to closed-loop cooling towers and air-cooled chillers for the server halls.
- Noise: At 3,200 acres the site has large buffer zones. Modeling predicts 55 dB at the nearest residence, about the volume of a normal conversation.
- Air: SO₂ and NOₓ emissions are projected to drop > 90 % and ≈ 80 % respectively, based on EPA-approved dispersion models released in August 2025.
How big is the national trend?
- Goldman Sachs Research forecasts a 165 % jump in global data-center power demand by 2030 versus 2023 levels.
- In the U.S., data centers could consume 12 % of all electricity by 2028, up from 8.9 % in 2023.
- Pennsylvania alone has eleven coal-to-data-center conversions in permitting or construction stages, making it the densest brown-field AI cluster outside of Northern Virginia.
