New research has possibly given a boost to the idea of carbon capture, indicating that CO2 is sometimes held dissolved in underground water for millions of years. However, it is acknowledged that CO2 contained in subterranean water is prone to bubble out again, and often does so - famously at naturally-sparkling springs, for instance.
The new information comes from a novel carbon-sequestration study carried out by government-funded researchers in the UK and Canada. Rather than using computer modelling, the scientists examined nine gas fields in North America, China and Europe. They used isotopes of carbon and noble trace gases (helium, neon) as tracers to work out what had happened to CO2 naturally present in the ground many millennia in the past.
There are two theories as to what might happen to CO2 injected into old gas fields, as is called for by many carbon-sequestration schemes. It might be dissolved in water - "like bottled sparkling water", as the British government notes, using this as justification for the assertion that "carbon capture has a sparkling future".
The alternative thing that might happen to CO2 is that it might react with the rocks around it to form carbonate minerals. But, according to the Brit and Canadian boffins, this isn't much of a factor. They say that in seven of their gas fields, almost all the carbon went into water rather than rocks; in the remaining two, at least 82 per cent did.
Lead author on the study Stuart Gilfillan, who was doing his PhD at Manchester Uni during the research and is now employed at the Scottish Centre for Carbon Storage, plainly believes that the fizzy-water results offer an ironclad case that carbon storage underground will work.
"We already know that oil and gas have been stored safely in oil and gas fields over millions of years," he says.
"Our study clearly shows that the carbon dioxide has been stored naturally and safely in underground water in these fields."
The study is published as a letter to heavyweight boffinry journal Nature: subscribers can read it here.
But it may not be time to rejoice and fire up that new coal-fired power station just yet - or try to persuade the Chinese and Indians to stick capture kit on their rapidly-multiplying coal stations, as the Telegraph suggests.