Cross-posted from the Natural Resources Defense Council.

For Earth Day, Steve Hayward of the American Enterprise Institute posted this shocker: “Energy Fact of the Week: Sulfur Dioxide Emissions from Coal Have Declined 54 Percent.” He includes some nice government charts, which I’m sure he won’t mind my reproducing below.

But from Hayward’s blog, you’d think this happened by itself!

The chief causes of this decline are technology — cost-effective “scrubbers” to remove sulfur dioxide from the waste stream — and resource substitution: We started using much more low-sulfur coal from the western United States.

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No mention of the Clean Air Act’s acid rain program — the limits on sulfur dioxide emissions established in the 1990 Clean Air Act. Without the Clean Air Act’s pollution limits, this scrubber technology and switch to lower-sulfur coal would never have happened. Why install pollution controls or use cleaner fuels if you can dump all your pollution in the atmosphere for free?

Who could doubt this? Well, Hayward just slyly omits any mention of the role of the Clean Air Act. But the good folks at the Heritage Foundation go farther, suggesting that the magic happens despite the Clean Air Act. See my colleague Laurie Johnson’s take-down of this nonsense here.

Let’s not forget, on this hyper-partisan Earth Day 2011, that the acid rain curbs were proposed in 1989 by President George H.W. Bush and adopted by Congress the next year with broad bipartisan support.

And this was — dare I say it — the world-premiere “cap-and-trade” program! Proposed by Republicans! Enacted by both parties! Carried out without a hitch by Republican and Democratic presidents, at a fraction of the predicted cost!

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Hey, maybe we could use this cool idea to curb the dangerous carbon pollution that’s driving global warming!

Oh, never mind.

Coal consumption and SO2 emissions

EPA projections of so2 emissions through 2035