from BBC

The hunt for heat: Drilling the deepest holes on Earth

by Norman Miller

Getty Images Tapping into the heat emitted by the Earth is relatively easy in places such as Iceland where it is close to the surface (Credit: Getty Images)
Tapping into the heat emitted by the Earth is relatively easy in places such as Iceland where it is close to the surface (Credit: Getty Images)

Beneath our feet is an almost limitless source of energy, but while a few lucky locations have geothermal heat close to the surface, the rest of the world will need to dig a lot deeper. The challenge is how to get deep enough.

There are some spots around the world where energy literally bubbles to the surface. In Iceland, home to more than 200 volcanoes and dozens of natural hot springs, tapping into this energy isn’t hard. Dotted around the country are steaming pools of water, heated by the geothermal fires that burn just below the crust. Boiling jets of water and steam are thrown into the air by geysers.

Iceland now heats 85% of its houses with this geothermal energy, while 25% of the country’s electricity also comes from power stations that harness this heat from underground. It’s an appealing prospect – an almost limitless supply of energy waiting to be tapped.  

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