President Obama's Environmental Protection Agency announced a new set of rules Monday that will make it practically impossible to do something that the marketplace has already decided is a dumb idea: Build more coal-fired power plants.
The move is a significant step toward getting a handle on the amount of climate-changing greenhouse gases American industry pumps into the atmosphere every day.
Except for 15 planned facilities that already have construction permits, the new EPA rules will hold any future coal-burning power plants to emissions of no more than 1,000 pounds of carbon dioxide per megawatt hour. That's less than half of the rate of CO2 emissions that existing coal plants disgorge on average, and just a bit below the average emissions for existing power plants fueled by natural gas. Natural-gas plants now on the drawing board should easily meet the standards.
Coal plants could get around that rule by meeting alternative pollution-control standards, or by implementing some means of capturing and storing the CO2 that would otherwise float away. But developing such carbon-capture technology on an industrial scale is something that has so far eluded us. So the likelihood is that the era of coal-powered electric generation appears on its way out.
And that's good news for the planet. Power plants create some 40 percent of the nation's greenhouse gas emissions, and coal is the largest share of that.
If private industry were scrambling to build more coal-fired plants, this rule might be a problem. But it isn't. The market has moved on, reasoning that coal is just too expensive, and too unpopular, to compete with much cheaper, and much more socially acceptable, natural gas.
Republican protests that the virtual ban on new coal-fired plants will jack up electric rates or, worse, choke off the supply of juice to our energy-hungry society, are not supported by any reputable survey or study.
The new rules, meanwhile, don't touch existing coal-powered installations. Previous plans to set rules for older plants, or at least to push them into compliance when they upgrade or expand, were set aside under political pressure last year, and EPA Administrator Lisa Jackson said that there are no immediate plans to revive them.
But setting firm rules for new facilities, combined with the move toward natural gas, is likely to mean that the old coal-burning plants will be allowed to wear out and die, replaced by cleaner sources of energy that are dictated both by law and by the market.