I was curious about what particular compounds are being sent into the air, and the New York Times (through archive is) was happy to tell me.

Less mentioned has been the pollution from the scores of gas-burning plants that will power these data centers. When the El Paso facility’s power plant is complete, it could emit as much planet-warming carbon dioxide in a year as 360,000 gasoline-powered passenger vehicles.

They would also produce harmful pollutants including particulate matter, formaldehyde, and smog-forming nitrogen oxides that can contribute to heart disease, asthma, lung cancer, strokes and other ailments in people living nearby.

They sent a required legal notice to two data center developers, the E.P.A., and Texas alleging that the developers sought to bypass stricter pollution rules by seeking four fast-tracked permits for two power plants that will ultimately have 151 diesel-burning generators. Compared to natural gas, diesel when burned produces more nitrogen oxide, carbon dioxide, and sulfur oxide as well as more particulate matter.

I knew of the CO~2~, NO~X~, and SO~X~, though the CH~2~O is one I didn't know about.