Sometimes it’s hard to find progress in public policy, especially in the energy sector, where a natural gas boom and new nuclear plant construction have been the big stories of late. But I am nothing if not a striver. So I’ve found the genuinely good news that ten more old, dirty coal-fired power plants will be shuttered.

Two utility companies announced the closure of 10 aging U.S. power plants Wednesday, a move environmental groups hailed as a major victory even as critics warned it could raise the price of electricity.

Midwest Generation, which had come under intense pressure from environmental activists, Chicago residents and Chicago Mayor Rahm Emanuel, said it will retire its Fisk Generating Station in 2012 and Crawford Generating Station in 2014. Both have been operating for decades in the middle of the city’s southwest side [...]

GenOn Energy, meanwhile, cited the same reason as it announced it will deactivate eight power plants — seven fired by coal and one by natural gas — between June 2012 and May 2015.

In its announcement, GenOn outlined a schedule for closing 3,140 megawatts of generation capacity in Ohio, Pennsylvania and New Jersey “because forecasted returns on investments necessary to comply with environmental regulations are insufficient.”

I don’t mind these companies blaming the regulatory state for these shutdowns. The regulatory state, in this specific case, is doing its job. These coal-fired plants generate as much pollution as they do power, to the detriment of the public health of hundreds of thousands of nearby residents and billions all over the world, given the greenhouse gas pollution. I remember the President, in one of his less cautious moments, saying that all these power plants will have to go. He’s right, because the regulatory agencies are forcing these plants to pay for part of their externalities, the public cost of their practices. And the companies cannot make a profit if they have to pay for those externalities.

The Sierra Club and other environmental justice groups have been working on coal plant shutdowns for many years now. They have a goal of retiring 105,000 megawatts of coal-fired generation by 2015, and with these announcements they are now almost halfway there (around 43,000 megawatts). They don’t get a lot of publicity, but it’s important work on the front lines to force a transition to our energy infrastructure. We appear to be moving toward a bridge of natural gas and nuclear rather than the real solution of renewables. But it’s definitely an advance.