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Volcanic Magma Could Provide Geothermal Energy

BY Ariel Schwartz | 02-17-2011 | 3:58 PM

magma

Iceland, land of unpredictable (and unpronounceable) volcanoes, has long used hot water and steam produced by volcanic rocks to heat its homes. But now the country may have a new energy resource: magma, or underground lava.

In 2009, a team of researchers drilling a 15,000-foot-deep geothermal well in Iceland's Krafla volcano stumbled upon magma, which was flowing into the well at a depth of 6,900 feet--only the second time magma has slipped into a geothermal well during drilling.

The incident forced the scientists to quit drilling. And that's when they figured out that the magma could be used as an energy source. PhysOrg explains:

"When the well was tested high pressure dry steam flowed to the surface with a temperature of 400 degrees Celsius or 750 degrees Fahrenheit, coming from a depth shallower than the magma," Elders [a geology professor at UC Riverside] said. He and colleagues estimated that this steam could generate 25 megawatts of electricity if passed through a suitable turbine--enough electricity to power 25,000 to 30,000 homes.

In comparison, most high-temperature geothermal wells only generate five to eight megawatts of electricity.

The researchers' happy accident means that magma can now be used as a geothermal energy source wherever shallow sources of magma are found--both in Iceland and in other places where young volcanic rocks exist. Not sure it's enough upside to living in a region where lava could flow down your block at any time, but it's something.

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