power plantThe EPA made an announcement today that lots of folks seem to be misinterpreting as “proposed regulations on power plants.” That’s not what they are.

What was announced today is the “tailoring” rule; it establishes that when the EPA regulates stationary sources, it will only regulate those that emit more than 25,000 tons. This is a modification of the threshold now in the Clean Air Act, which is 250 tons. If EPA regulated every source emitting more than 250 tons, it would be a nightmare (churches! schools! marathons!). There’s some dispute about whether the EPA is legally allowed to do this; not surprisingly, I hear different things from different sides of the aisle. It is sure to be litigated.

This announcement has been expected for a while, by the way, so it’s not quite so epochal as some are making out.

When the new EPA fuel economy regulations go into effect in 2010, that will automatically — as in, by law — trigger regulations of stationary sources. Such sources will have to get permits showing that they’ve used Best Available Control Technology to reduce CO2. BACT has not yet been defined for CO2. That’s going to be a huge and incredibly contentious fight. Now, at least, we know when the fight will start.

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If you’re interested, I wrote a comprehensive rundown on EPA regulation of CO2. It explains what to expect in clear language. Also it has bunnies.