Iceland’s Plan to Get Energy from Hot Magma Is Really Cool

Iceland boasts some of the most alien geography on Earth, and now the Nordic country is tapping its unique natural phenomena as a potential—and highly volatile—source of future energy.

An intrepid team of Icelandic researchers hopes that magma, or molten rock, might one day become a super-powerful geothermal energy source.

Right now, the Iceland Deep Drilling Project (IDDP) is attempting to harvest power from magma beneath a lava flow in Reykjanes. If they succeed, their achievement "could lead to a revolution in the energy efficiency of high-temperature geothermal areas worldwide," said Wilfred Elders, a professor emeritus of geology at the University of California, Riverside who was involved with a previous IDDP project.

In order to hit magma, a drilling rig (affectionately named "Thor") is boring down between two tectonic plates, in a boundary region known as the Mid-Atlantic Ridge. Most of this ridge is underwater, but parts of it, like the seismically active Reykjanes Ridge that runs right through Iceland, are visible above sea level. The rig will need to penetrate a depth of around three miles below the surface, deepening an existing well, and withstand temperatures up to 900°F, said IDDP.

While this might sound like a disaster waiting to happen, researchers are fairly certain of what to expect, since this will be their second foray into subterranean power.

In 2009, an IDDP rig located in Krafla, northeast Iceland, accidentally struck a magma reservoir just over a mile underground. Excited about the prospects of new geothermal energy, the project partnered with Iceland's National Power Company, and installed a perforated steel casing at the bottom of the well. This successfully allowed the flow of magma to create superheated, extremely pressurized steam at temperatures exceeding 800°F—at the time, a world record for geothermal heat.

Power created by the Krafla borehole was never fed back into the grid, and the project was shuttered in 2012 after a critical valve needed repairing.

Some experts have also expressed concern that opening veins into magma pockets could be unstable, or even dangerous to human life.

In 2006, a geothermal drilling project in Basel, Switzerland plunged too deep, triggering a 3.4 magnitude earthquake after engineers bored three miles into the Earth. That same year, in East Java, Indonesia, it was argued that a gas exploration project set off an enormous mud volcano that caused 30,000 people to lose their homes.

"They can become very dynamic, raised in pressure, and even force magma to the surface. But if it's not activated [by seismic activity that causes magma chambers to fill], then there's no reason to expect a violent eruption, even if you drill into it," Gillian Foulger, professor of geophysics at Durham University who worked at Krafla, told The Conversation in 2014.

"Having said that, with only one experimental account to go on, it wouldn't be a good idea to drill like this in a volcanic region anywhere near a city."

Other geothermal energy sources, such as The Geysers in California, are produced by running cold water down through hot, dry rocks, which produces steam that can be converted into energy. But with magma power, the IDDP is hoping to discover supercritical water, which is a powerful fluid energy source "that can be as dense as a liquid but at the same time flow as easily as a gas."

The Krafla borehole had an energy capacity reaching 36 megawatts of electrical power, which is less than the average 547 megawatts of US coal-fired power plants, but more than the world's largest wind turbine, the SeaTitan, which has a capacity of 10 megawatts.

As of now, approximately 71 percent of Iceland's annual energy comes from hydropower, while 29 percent is produced geothermally. In the capital city of Reykjavik, almost all residential properties are heated using geothermal energy.

"Most people faced with tapping into a magma chamber would pack their bags and leave," said Foulger. "But when life gives you lemons, you make lemonade."