AI Data Center Boom May Undo 15 Years of US Emission Cuts

A Sierra Club internal analysis warns that the boom in fossil fuel plants built to power AI data centers could wipe out 15 years of greenhouse gas cuts made by the US power sector.

The group estimates that if planned AI projects are included, US power sector CO2 emissions could reach 2.1 billion tons by 2030, up 618 million tons from 2025 — a jump of about 42%.

To meet the huge power demand, many developers are turning to natural gas and building their own power plants to skip long waits to connect to the grid. These self-built plants could emit more than 460 million tons, roughly equal to Mexico's yearly total.

Self-built plants add local air pollution and greenhouse gases, sparking more opposition to data center projects across the US. Forecasts for future emissions still vary widely — the gap between the highest and lowest estimates is bigger than the combined power use of California and Florida.