Hank Green: Hello! I'm Hank Green, and this SciShow News.

Almost all the power that we use here on Earth came from the sun. Solar, coal, oil, wood, wind, ethanol - if you trace it back, it's all just captured sunlight. But one of the most massively powerful forces we have here on Earth, a store of energy so gigantic that it liquefies trillions upon trillions of tonnes of rock, is independent from the sun's energy inputs.

It's the pressure of the Earth pushing down on itself, heating its interior to such dramatic temperatures that every once in a while, a pimple while erupt on its surface, spewing rock kilometers into the air, leaking lava from the wound. If only we could capture that energy. Maybe we can.

(Intro)

Hank: Our thirst for oil has made us really good at digging deep holes, but scientists in Iceland have been digging super deep holes for that other source of power: geothermal energy. The deeper you go, the hotter it gets. In Iceland, thirty percent of the electricity is already derived from geothermal forces; it is a very geologically active place. The word geyser in English is actually derived from the name of a geyser in Iceland.

The process is pretty simple at the surface level: just drill a hole kilometers into the Earth and then pour some water down there. The water boils, increasing dramatically in volume, pushing through a turbine which generates electricity.

But in 2009, scientists with the Icelandic Deep Drilling Project, or IDDP, hit something of a snag when one of their boreholes stopping drilling through rock and started drilling into magma. The temperature jumped from 400 degrees Celsius to over 1000 degrees Celsius. This wasn't the first time this had happened, actually, but while previous teams had seen it as a project-ending failure, plugging the hole with concrete and moving on, the IDDP decided to take those lemons and make some lemonade. Some very, very hot lemonade.

They cemented a steel casing into the hole, allowed the heat to build up, poured some water in, and boom. Over the course of two years, steam gushed out of the hole at record high temperatures, extracting enough power to generate thirty-six megawatts of constant power, though that power was not captured.

Geothermal power is limited mostly by the heat of the rock engineers are boiling the water in. In this hole, the magma was close to the surface and not under any significant pressure, which is why it didn't come bubbling back up out of the hole. The result was a far more efficient process that produced far more power than the average geothermal well. Keeping the well running was a constant challenge, as steam of this temperature and pressure had never been seen before in geothermal plants, and as they were attempting to hook the new well into a nearby geothermal power plant, a valve failed, and the well had to be permanently closed.

The papers springing from this two-year-long experiment in magma power - the first ever of its kind - took over the entire January edition of the journal Geothermics. All of it. There were no papers in the entire journal about anything else. This could represent a massive leap forward for geothermal power, though most places do not have magma anywhere near this close to the surface of the Earth, and the risk of punching through a high pressure magma pocket is significant enough that scientists recommend not trying this anywhere near a population center, but the potential for expanding this clean source of energy - already producing ten terawatts of electricity globally - is very good news indeed. Volcano power!

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