A radical new 'negative emissions' power plant has begun operations in Iceland.

The EU-backed project at one of the world's largest geothermal power plants in Hellisheidi, Iceland, will capture CO2 from ambient air for permanent storage underground.

Although still at pilot scale, researchers hope the scheme could be scaled up across the globe.

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One of the world’s largest geothermal power plants in Hellisheidi, Iceland, where CO2 is currently injected and mineralized at an industrial scale in a groundbreaking trial

The CO2 reacts with the basaltic bedrock and forms solid minerals, creating a permanent storage solution.

The team behind it this week confirmed a testing phase has started during which the CO2 is captured from ambient air, bound to water, and sent to more than 700 meters underground.

Currently the pilot system captures only 50 metric tons CO2, each year, about the same emitted by a single US household.

The finished product: Basalt core containing carbonates

However, its inventors hope it can be scaled up.

'The potential of scaling-up our technology in combination with CO2 storage, is enormous,' said Christoph Gebald, Founder and CEO at Climeworks.

'Our plan is to offer carbon removal to individuals, corporates and organizations as a means to reverse their non-avoidable carbon emissions.'

Edda Sif Aradóttir, CarbFix project leader at Reykjavik Energy said: 'We have developed CarbFix at a unique location here in Iceland and proved that we can permanently turn this greenhouse gas into rock.

'By imitating natural processes this happens in less than two years.'

HOW CO2 IS TURNED INTO STONE CO2 is captured from ambient air, bound to water, and sent to more than 700 meters underground. There the CO2 reacts with the basaltic bedrock and forms solid minerals, creating a permanent storage solution. Climeworks' technology draws in ambient air and captures the CO2 with a patented filter. The CO2 reacts with the basaltic bedrock and forms solid minerals, creating a permanent storage solution The filter is then heated with low-grade heat from the geothermal plant to release the pure CO2 which then can be stored underground. During the trial Climeworks will test how its technology works with the specific weather conditions at the location in the South West of Iceland. Advertisement

The firm is also pursuing other projects.

In the countryside near Zurich, Swiss company Climeworks began to suck greenhouse gases from thin air in May with giant fans and filters in a $23 million project that it calls the world's first 'commercial carbon dioxide capture plant'.

Worldwide, 'direct air capture' research by a handful of companies such as Climeworks has gained tens of millions of dollars in recent years from sources including governments, Microsoft founder Bill Gates and the European Space Agency.

If buried underground, vast amounts of greenhouse gases extracted from the air would help reduce global temperatures, a radical step beyond cuts in emissions that are the main focus of the Paris Agreement.

Climeworks' technology draws in ambient air and captures the CO2 with a patented filter.

Climeworks reckons it now costs about $600 to extract a tonne of carbon dioxide from the air and the plant's full capacity due by the end of 2017 is only 900 tonnes a year.

That's equivalent to the annual emissions of only 45 Americans.

And Climeworks sells the gas, at a loss, to nearby greenhouses as a fertiliser to grow tomatoes and cucumbers and has a partnership with carmaker Audi, which hopes to use carbon in greener fuels.

Jan Wurzbacher, director and founder of Climeworks, says the company has planet-altering ambitions by cutting costs to about $100 a tonne and capturing one percent of global man-made carbon emissions a year by 2025.

'Since the Paris Agreement, the business substantially changed,' he said, with a shift in investor and shareholder interest away from industrial uses of carbon to curbing climate change.

Scientists are sucking carbon dioxide from the air with giant fans and preparing to release chemicals from a balloon to dim the sun's rays as part of a climate engineering push to cool the planet.

In the countryside near Zurich, Swiss company Climeworks began to suck greenhouse gases from thin air in May with giant fans and filters in a $23 million project that it calls the world's first 'commercial carbon dioxide capture plant'.

Backers say the risky, often expensive projects are urgently needed to find ways of meeting the goals of the Paris climate deal to curb global warming that researchers blame for causing more heatwaves, downpours and rising sea levels.

The United Nations says the targets are way off track and will not be met simply by reducing emissions for example from factories or cars - particularly after U.S. President Donald Trump's decision to pull out of the 2015 pact.

CONTROVERSY OVER GEO-ENGINEERING The Paris Agreement seeks to limit a rise in world temperatures this century to less than 2 degrees Celsius (3.6 Fahrenheit), ideally 1.5C (2.7F) above pre-industrial times. But U.N. data show that current plans for cuts in emissions will be insufficient, especially without the United States, and that the world will have to switch to net 'negative emissions' this century by extracting carbon from nature. Riskier 'geo-engineering' solutions could be a backstop, such as dimming the world's sunshine, dumping iron into the oceans to soak up carbon, or trying to create clouds. But, some research has suggested that geo-engineering with sun-dimming chemicals, for instance, could affect global weather patterns and disrupt vital monsoons. And many experts fear that pinning hopes on any technology to fix climate change is a distraction from cuts in emissions blamed for heating the planet. Advertisement

But penalties for factories, power plants and cars to emit carbon dioxide into the atmosphere are low or non-existent.

It costs 5 euros ($5.82) a tonne in the European Union.

Climeworks reckons it now costs about $600 to extract a tonne of carbon dioxide from the air and the plant's full capacity due by the end of 2017 is only 900 tonnes a year

RISING GLOBAL TEMPERATURES Year Temperature increase (°C relative to average temperature 1961-1990) 2016 0.77 2015 0.76 2014 0.58 2013 0.51 2012 0.47 2011 0.42 2010 0.56 2009 0.51 2008 0.39 2007 0.49 2006 0.51 2005 0.54 2004 0.45 2003 0.51 2002 0.5 2001 0.44 2000 0.29

And isolating carbon dioxide is complex because the gas makes up just 0.04 percent of the air.

Pure carbon dioxide delivered by trucks, for use in greenhouses or to make drinks fizzy, costs up to about $300 a tonne in Switzerland.

Other companies involved in direct air capture include Carbon Engineering in Canada, Global Thermostat in the United States and Skytree in the Netherlands, a spinoff of the European Space Agency originally set up to find ways to filter out carbon dioxide breathed out by astronauts in spacecrafts.

The Paris Agreement seeks to limit a rise in world temperatures this century to less than 2 degrees Celsius (3.6 Fahrenheit), ideally 1.5C (2.7F) above pre-industrial times.

But U.N. data show that current plans for cuts in emissions will be insufficient, especially without the United States, and that the world will have to switch to net 'negative emissions' this century by extracting carbon from nature.

Riskier 'geo-engineering' solutions could be a backstop, such as dimming the world's sunshine, dumping iron into the oceans to soak up carbon, or trying to create clouds.

Among new university research, a Harvard geo-engineering project into dimming sunlight to cool the planet set up in 2016 has raised $7.5 million from private donors.

In the countryside near Zurich, Swiss company Climeworks began to suck greenhouse gases from thin air in May with giant fans and filters in a $23 million project that it calls the world's first 'commercial carbon dioxide capture plant'

It plans a first outdoor experiment in 2018 above Arizona.

'If you want to be confident to get to 1.5 degrees you need to have solar geo-engineering,' said David Keith, of Harvard.

Keith's team aims to release about 1 kilo (2.2 lbs) of sun dimming material, perhaps calcium carbonate, from a high-altitude balloon above Arizona next year in a tiny experiment to see how it affects the microphysics of the stratosphere.

'I don't think it's science fiction ... to me it's normal atmospheric science,' he said.