If the first thing you think of when I say "Rwanda" is "Don Cheadle looking worried while a radio booms 'Hutu Power!' in a basso profundo," it's time you updated your thinking. The country is currently looking into meeting its need for electricity by tapping into the hot rocks that underlie much of the country, which is in Africa's geologically active Rift Valley.

While countries like India try to fuel their growth with the kind of fossil fuels that destroy air quality and are going to run out anyway, Rwanda is taking a cue from its neighbor, Kenya, which estimates it has as much as 10 gigawatts of geothermal capacity. That's enough to meet the needs of the entire country and export the surplus.

Rwanda's plans are a bit less ambitious — they think they can tap about 700 megwatts, at least initially. That's not bad considering that, properly managed, geothermal energy is steady, carbon-free baseload power, like a nuke plant minus the potential for meltdown.

The lesson is, sometimes it's good to live near a volcano, because they are a source of free energy. Or if not free, at least comparable in price to the dirty, unsustainable kind.

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