Waste heat: It's everywhere, and we're wasting it. (Hence the name.) Giant industrial processes throw off enormous amounts of the stuff, all of it not quite hot enough to be usable in conventional power generation.

That's where the waste heat industry comes in. Using liquids that boil at temperatures significantly lower than water, they've created systems that can use waste heat from factories to produce electricity. And now they want the government to recognize this power as another form of renewable energy — including providing tax incentives.

It could totally happen, too. Obama recently visited a pioneer in the field, ElectraTherm, whose "Green Machine" can be hooked up to everything from existing oil and gas wells to biomass burning facilities in order to produce extra electricity.

ElectraTherm’s motto is "Heat is Power," and the company argues that harvesting the enormous volumes of untapped waste heat in the U.S. could lead to "the cheapest form of new energy generation." Of course, most of it would be used on-site, which is a good thing: it means no new transmission lines.

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It's distributed power! Or it's efficiency. Who cares: it works.

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