Could British homes be powered by Icelandic volcano?

Harnessing the power of Iceland’s volcanoes to provide energy to British homes is one of those ideas that resurfaces every few years, but sounds too good – or whacky – to be true.

However, interest from a clutch of international companies in a geothermal project in northern Iceland suggests the idea is not just achievable but commercially viable too.

Scientists working on the Krafla Magma Testbed plan to drill more than 2km below the Earth’s crust into a molten magma lake, starting a process they say could see the UK receiving energy from Iceland’s volcanoes within 20 years.

In an experiment due to begin in 2020, the researchers will drill an initial borehole down to the magma body, into which water can be pumped through reinforced U-shaped pipes. The resulting “supercritical steam” could, in theory, be used to power turbines and the energy generated sent across the North Atlantic via underwater cables.

While geothermal power already generates a quarter of Iceland’s electricity production, on a global scale the sector has failed to flourish in the same way as solar or wind. Held back by high upfront development costs, it currently produces less than 1% of the world’s electricity, according to the World Energy Council.

However, new technology of the type being piloted in Krafla could accelerate the sector’s growth, according to Freysteinn Sigmundsson, a geophysicist at the University of Iceland and an investigator on the project.

Professor Yan Lavallée, a volcanology and magma research chair at Liverpool University, says the renewable potential is enormous. “Even a small body of magma in the order of a fraction of a cubic kilometre could power a whole country the size of the UK,” he says, adding that the possibility of storing the energy generated in large batteries or old mines is also under discussion.

The promise of bountiful, clean volcano power appears to be attracting the attention of a host of large corporations, including those from the fossil fuel and mining sectors.

“We have had discussions with a number of international oil and gas companies,” says John Ludden, the director of the British Geological Survey (BGS), which is coordinating the Krafla project with Iceland’s Geothermal Research Group.

The Norwegian oil and gas giant Statoil confirmed an “informal dialogue” with the Krafla project, while Canada’s Falco Resources, a mining company, has part-funded a research post that is exploring collaborative work with the Krafla team.

The researchers are also working with US-based Sandia National Laboratories, a nuclear contractor to the US government, to assess how to deal with magma at temperatures of 900C, says Ludden.

“It’s not impossible to imagine that Iceland could send 2GW of energy at a time to the UK, Holland or Denmark via underwater cables,” he says – enough to power around 1.5m homes. “Perhaps that could happen in the next two decades.”

Political and financial challenges

Those underwater cables would, of course, come at a cost: one assessment (pdf) puts the price of a 1,000km-long interconnector across the North Atlantic at up to €3.5bn (£2.7bn), almost twice the cost of the London Array, one of the largest offshore wind farms in the world.

Hordur Arnarson, CEO of Icelandic utility Landsvirkjun, which will develop the Krafla site, has warned that his company would need fixed price guarantees and long-term contracts, along the lines of the support given to the Hinkley Point C nuclear reactor.

He has also previously raised concerns that Brexit could complicate the process. However, a UK-Iceland joint task force concluded (pdf) last July – after the referendum – that there was a viable business case for such a connector, and the European commission has put the cable on its list of “projects of common interest”.

In any case, the cable would need five more years of assessments and preparatory work before construction could begin, according to Landsvirkjun, providing plenty of time for any opposition to organise.

In Iceland, people living near the Krafla site have been told a risk assessment involving them will take place, says Bjarni Pálsson, a project manager for Landsvirkjun. Researchers have said, so far, that they see no risk their drilling will trigger an eruption, and that they will insert magma flow sensors specifically geared to detect future eruptions.

Exporting the energy, rather than using it to boost domestic industry, is also likely to raise eyebrows. Pálsson describes exports as “just an option that the government is looking into”.

“It is definitely a political issue and it will have to go through a lot of dialogue before being realised,” he says.

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• This article was amended on 19 May 2017. An earlier version said that the pipeline would bring energy from Iceland to the UK across the North Sea. This has been corrected to say the North Atlantic.