Results show quick CO2 ‘fix’ feasibility – but its future rests in government hands

The CarbFix project is trapping natural CO2 emissions underground as Iceland seeks to offset emissions from other sources. Image credit: Reykjavik Energy

The CarbFix project is trapping natural CO2 emissions underground as Iceland seeks to offset emissions from other sources. Image credit: Reykjavik Energy

Although CO2 can stay in the atmosphere, trapping heat, for thousands of years scientists think they have turned it into rock in just a few months. Juerg Matter from the University of Southampton, UK, and his colleagues in the CarbFix project have injected 170 tons of pure CO2 into the reactive basalt underneath Iceland. Their findings suggest around 85% of it reacted with the rock over the short distance between injection and monitoring boreholes in less than one year.

“We think that was because all that CO2 precipitated out as carbonate minerals in the reservoir,” Juerg, who’s also an adjunct scientist at Lamont-Doherty Earth Observatory in New York, told me. “To really prove it this summer we will drill a borehole into the injection reservoir to retrieve rock core samples.” But the CarbFix team has also emphasised this week that it will take higher carbon prices for this and other carbon capture and storage technology to fulfil their potential.

The latest UN Intergovernmental Panel on Climate Change (IPCC) says the cheapest way to avoid dangerous climate change is to stop using fossil fuels and switch to renewable energy. However time’s running out on that option, and the IPCC report therefore highlights the probable need to suck CO2 from the air. But before we capture CO2 straight out of the air, or even from the chimneys of power stations, we need somewhere to put it. Currently captured CO2 is simply pumped and stored underground as a gas, meaning care is needed to choose reservoirs that won’t leak. “Storage options right now are mainly in depleted gas and oil fields, in sedimentary rocks,” Juerg said.

In the air, CO2 eventually reacts with basalt naturally, but that process is far too slow to balance out what humans are emitting. Since 2007 the CarbFix team has been working to see if they can speed that process up by forcing CO2 underground. Not only would this quickly turn the gas into minerals and prevent leak worries, it would also greatly expand the number of places it could be stored. “The storage potential is just huge, there’s billions of tons of reservoir, because basically all the ocean floor is basalt,” Juerg highlighted. Read the rest of this entry »

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How ocean data helped reveal the climate beast

Wally Broecker's famous quote on display at California Academy of Sciences.  Image copyright: Jinx McCombs, used via Flickr Creative Commons license

Wally Broecker’s famous quote on display at California Academy of Sciences. Image copyright: Jinx McCombs, used via Flickr Creative Commons license

  • This is part two of a two-part post. Read part one here.

On the wall of Wally Broecker’s building at the Lamont-Doherty Earth Observatory hangs a 16-foot long terry-cloth snake, blue with pink spots, that he calls the ‘climate beast’. Left in his office as a surprise by his workmates, its name refers to one of Wally’s most powerful quotes about the climate: “If you’re living with an angry beast, you shouldn’t poke it with a sharp stick.”

Today, the sharp stick is the CO2 we’re emitting by burning fossil fuels, which Wally was warning about by 1975. By that time he had also helped confirm that throughout history, changes in Earth’s orbit have given the climate beast regular kicks, triggering rapid exits from ice ages. He became obsessed with the idea that climate had changed abruptly in the past, and the idea we could provoke the ‘angry beast’ into doing it again.

Among the many samples that Wally was carbon dating, from the late 1950s onwards he was getting treasure from the oceans. Pouring sulphuric acid into seawater, he could convert dissolved carbonate back into CO2 gas that he could then carbon date. And though nuclear weapon tests had previously messed with Wally’s results, they actually turned out to help improved our knowledge of the oceans. The H-bomb tests produced more of the radioactive carbon-14 his technique counts, and as that spike moved through the oceans, Wally could track how fast they absorbed that CO2.

In the 1970s, as Wally and a large team of other scientists sailed on RV Melville and RV Knorr tracking such chemicals across the planet’s oceans, a debate raged. Was cutting down forests releasing more CO2 than burning fossil fuels? Dave Keeling’s measurements showed the amount of CO2 being added to the air was about half the amount produced by fossil fuels. But plants and the oceans could be taking up huge amounts, scientists argued. Thanks to the H-bomb carbon, Wally’s team found the CO2 going into the oceans was just 1/3 of what fossil fuels had emitted. Faster-growing plants therefore seemed to be balancing out the impact of deforestation, and taking up the remaining 1/6 portion of the fossil fuel emissions. Read the rest of this entry »

The joker who brought climate science out of the cold

Wally Broecker, when he registered for the Columbia University geology department in 1953. Credit: Department of Earth and Environmental Engineering Archives, Columbia University

Wally Broecker, when he registered for the Columbia University geology department in 1953. Credit: Department of Earth and Environmental Engineering Archives, Columbia University

In Los Angeles on September 1 1955, the day temperatures reached a new record of 43°C, Wally Broecker stood, sweating, giving the first scientific talk of his life. He could scarcely have guessed where the new method he was telling an audience of sleepy archaeologists about, called radiocarbon dating, would send him. But thanks in part to its messages from history he would help spawn the phrase ‘global warming’ and warn of its effects, which have today pushed temperatures even higher.

Wally grew up and started college on the outskirts of Chicago, Illinois, good at maths, but largely uninterested in science. But college-mate Paul Gast steered his career sciencewards by helping get him a summer job at the new Lamont Geological Observatory that Paul had recently started working at. On June 15, 1952 Wally and pregnant wife Grace drove 800 miles to the Palisades, New York mansion Columbia University had inherited, and set up the observatory in. There, in the basement, Wally worked in and soon practically ran Laurence Kulp’s radiocarbon lab. Rather than lose him at the end of the summer Laurence organised for Wally to transfer to Columbia and stay working at Lamont, where he has remained ever since.

Taking advantage of the slow decay of a rare, radioactive form of carbon – carbon-14 – radiocarbon dating was in its infancy. The balance between carbon-14 and the usual form, carbon-12, is quite steady in CO2 in the air, and also in living plants that take up the gas as they grow. But when plants die, the carbon-14 they contain slowly decays to nitrogen. Measuring the ratio between the two forms of carbon, scientists can tell when the plants had died. But in 1952, Laurence’s lab was getting inconsistent readings, with carbon-14 counts sometimes coming out too high, even after Wally had fixed a problem with the equipment. Then Wally realised the problem came from outside the lab. The extra counts were coming from nuclear tests that had recently started over Nevada.

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CO2 for oil swap brings carbon capture viability closer

Oil and gas producer Denbury makes its case for its 300-mile plus “Green Pipeline” that transports CO2 for use in extracting more oil from old fields. University of Texas, Austin’s Carey King and colleagues have looked at the economics of using a larger network to store CO2 in underground saline aquifers.

For 314 miles from Donaldsonville, Louisiana, to Alvin, Texas a 24-inch diameter pipeline slithers under the landscape, dwarfing even the giant invasive snake species menacing the US. And while the Hastings Oil and Gas Field sits at the Texan end of the pipe, fossil fuels don’t flow along it: CO2 does. Rather than emit the greenhouse gas to the atmosphere, in Louisiana, Mosaic Phosphates Company’s Faustina Plant sends it to Texas. There the pipeline’s owner, Denbury, uses the CO2 to swill more oil out of the ageing Hastings field, leaving most of the CO2 trapped underground instead.

Denbury estimates that from 2014 it could get 10,000 tonnes of CO2 a day from industrial sources. Though that sounds a lot, it pales against the roughly 15 million tonnes the whole US emits each day. But what if Texas’ coal-fired power plants were hooked up to pipelines to both produce more oil from old fields and keep CO2 locked out of the atmosphere?

A team of University of Texas at Austin scientists have been looking at the financial details of how such a network might work. Though it could trap much more CO2 than burning the oil it gets out will emit, they find that such a scheme likely could not yet support itself. “If you capture CO2 from multiple coal-fired generators to produce oil and you want to have a net storage of CO2, the costs are still greater than the revenues,” UT Austin’s Carey King told me. “But the oil revenues do pay for the majority of the costs.”

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What Dave Keeling did ahead of his curve

Dave Keeling in front of the pier at Scripps Institution of Oceanography in San Diego, which houses a variety of measuring equipment. Credit: Scripps Institution of Oceanography

Dave Keeling in front of the pier at Scripps Institution of Oceanography in San Diego, which houses a variety of measuring equipment. Credit: Scripps Institution of Oceanography

On 18 May 1955, Charles David Keeling – Dave to most – set up camp near a footbridge over a river in Big Sur State Park in California. Armed with a set of five litre flasks containing nothing but vacuum, he planned to suck up air samples regularly over the 24 hours. At the time it may have seemed the latest uncertain step of a young man unsure how best to combine his interest in science and love of the outdoors. But instead it became the start of a lifelong quest to accurately measure the main gas that man is changing the world’s climate with: CO2.

“At the age of 27, the prospect of spending more time at Big Sur State Park to take suites of air and water samples instead of just a few didn’t seem objectionable, even if I had to get out of a sleeping bag several times in the night,” Dave wrote in his autobiography. “I did not anticipate that the procedures established in this first experiment would be the basis for much of the research that I would pursue over the next forty-odd years.”

Growing up in the midwest US near Chicago, Dave’s interest in science was kindled at age five, when his economist father introduced him to the wonders of astronomy. To show Dave how the seasons came about, together in their living room they circled a globe around a lamp, serving as the sun. Going through school during the Second World War, Dave took a special class in preflight aeronautics as well as the conventional sciences.

He then enrolled in the University of Illinois early, during the summer, to fit in a year of study before he reached the conscription age of 17. With limited science options available at this time of year, he chose to major in chemistry. “I didn’t particularly like chemistry and repeatedly doubted that I had made the right choice,” he recalled. But before the year – 1945 – was out, the war was over, and so Dave could continue his course. Chemistry students were expected to study economics, but Dave felt that he’d had enough economics at home. So he opted out of chemistry, ultimately getting a general liberal arts degree.

Yet he was still offered a place to study for a chemistry PhD at nearby Northwestern University with a friend of his mother’s. He took it without applying for any others, but later realised his previous studies had left him unprepared. “Accepting so soon was probably a mistake,” he wrote. Required to take a minor subject as part of his studies, Dave chose geology. His supervisor even suggested he might like to make this his major, though Dave declined, graduating in chemistry after a gruelling five years. And while his skills were in great demand from the post-war chemical industry Dave wanted a job that would let him work outside. So he applied for geology roles at universities, managing to find one at the California Institute of Technology. Read the rest of this entry »

Scientists spotlight rock’s role in carbon capture success

Equipment for monitoring seismic activity being deployed in a borehole at the Weyburn CO2 storage site in Saskatchewan, Canada. Credit: University of Bristol

Equipment for monitoring seismic activity being deployed in a borehole at the Weyburn CO2 storage site in Saskatchewan, Canada. Credit: University of Bristol

Climate change is a problem that many would like to bury – and indeed ‘burying’ CO2 deep underground might be needed to get it under control. And injecting the greenhouse gas among the rocks below us on a large scale is a serious option, if the storage sites are chosen carefully. That’s according to a study of three sites where ‘carbon capture and storage’ (CCS) has been done, published by University of Bristol’s James Verdon and his teammates this week. “Too often CCS is seen as a binary thing – it’ll either be brilliant or hopeless, depending on whether you are for or against,” James told me. “This study shows that every CCS site will be different – there won’t be a one size fits all solution.”

Scientists think it will be dangerous if global temperatures go more than 2°C above the pre-industrial average from 1850-1899. That’s recognised by governments in a non-binding climate change target in the Copenhagen Accord in 2009, where many also pledged actions to cut their CO2 emissions. But we continue to pump out ever more CO2, making the chances of sticking to the target through emission cuts alone ever slimmer.

CCS, which captures CO2 where lots would otherwise be released and then stores it where it can’t reach the air, is an alternative approach. Though the cost of the technology needed to do this has meant projects have been delayed and even abandoned, eight large-scale CCS projects are operational today. James has worked at two: Weyburn in Canada, and In Salah in Algeria. At a meeting of British CCS scientists he mentioned this to Andy Chadwick from the British Geological Survey in Nottingham, who had worked at the Sleipner CCS project in Norway. They realised that comparing the sites could help answer one of the biggest potential issues around CCS beyond cost: how rocks respond to CO2 injection. Read the rest of this entry »