Don’t swim too far from the shore in Iceland’s famous Blue Lagoon, or you will cook like a lobster.
At 240°C, mineral-rich water drilled from deep underground runs the neighbouring geothermal power plant, before cooling enough to bathe in. Now technology pioneered nearby offers another step to keeping carbon dioxide out of the atmosphere – and stopping the world overheating.
This new technology could help end the recent bad run for carbon capture and storage (CCS) – the process of taking carbon dioxide from power stations and industry and locking it away safely underground, in minerals or useful products.
In November, the UK government extended years of dithering by cancelling its flagship £1 billion (Dh4.8bn) CCS competition, disappointing contenders at Peterhead in Scotland and Drax in North Yorkshire. The Kemper County coal-fired power plant under construction in the US state of Mississippi, intended as a showpiece, has suffered years of delays and US$4bn of cost overruns.
The British delay is all the more puzzling as the country’s need for reliable low-carbon electricity grows. Rejecting home-grown solutions, the government keeps scratching its head over the monumentally expensive, French-Chinese, £18bn Hinkley Point nuclear power station.
But CCS remains essential. Despite renewable energy’s great advances, it will require massive amounts of batteries or other storage, or complementary power, to supply all our needs reliably. Many industrial processes, such as cement and steel manufacturing, release carbon dioxide and cannot run on renewables. And to reverse the worst impacts of climate change, we will eventually have to start actively removing carbon dioxide from the atmosphere.
At Hellisheidi, the world’s third-largest geothermal power plant, about an hour’s drive from the Blue Lagoon, the hot water brings up carbon dioxide. If released to the atmosphere, this would worsen climate change, exactly the outcome that clean-energy sources such as geothermal are intended to avoid.
Researchers injected the carbon dioxide back into the volcanic basalt rocks at the site, 400 to 500 metres underground, and found that more than 95 per cent of the gas reacted with minerals to form stone within two years.
Further confirmation of the security of underground storage comes from work by my former Cambridge professor, Mike Bickle, and colleagues, published in Nature Communications on Thursday, showing that natural carbon dioxide remains trapped for at least 100,000 years.
The Icelandic results are particularly encouraging for Oman and the UAE. Basalt is common throughout the world, but the Oman mountains are rich in another rock, peridotite, which is even better at reacting with carbon dioxide. There is enough peridotite here to absorb a thousand years of humanity’s CO2 pollution. Carbon dioxide can also be injected into ageing oilfields, a process under way in Abu Dhabi’s Rumaitha field.
Capturing the carbon dioxide from a power station’s emissions remains the most challenging step of the process. Although not technologically difficult, it is expensive and cuts the plant’s efficiency. In autumn 2014, Boundary Dam in Saskatchewan, Canada, came online as the world’s first full-scale coal power plant with carbon capture. Lessons here will be vital in bringing down costs – its owner SaskPower saying it could do the next project 25 per cent more cheaply.
Completely new combustion processes are also in development. In St Petersburg earlier this year, the British engineer Rodney Allam described to me his company’s radically new power plant, which burns gas in pure oxygen at high pressure, recycling carbon dioxide as the turbine’s working fluid. It is very fuel-efficient, captures carbon dioxide automatically and is more compact than conventional designs. The company, Net Power, is building a demonstration unit in Texas.
Naysayers like to point to the high cost of CCS and the stumbles of early projects without presenting viable alternatives. But from Canada and Texas to Iceland and Abu Dhabi, new technologies are emerging to make clean fossil fuels a reality, before the world grows intolerably hot.
Robin Mills is the chief executive of Qamar Energy and the author of The Myth of the Oil Crisis