As more and more countries around the world struggle to meet their carbon emission reduction targets, they are looking for all kinds of solutions to work around the problem. One of those is carbon capture and storage (CCS).

This atmospheric CO2 reduction method has however been under heavy fire for being hazardous for human health in case of leaks. But now research on 286 Italian sites where CO2 seeps from the soil naturally has shown there is little to worry about poisoning caused by CO2 leakage.

Carbon capture and storage

CCS involves the collection of CO2 at industrial sites or power stations before it can escape into the atmosphere. The captured gas is then liquefied and stored deep underground in porous rocks. Eventually the CO2 will dissolve in underground water flows.

Such storage sites have numerous barriers between the surface and storage level, inhibiting CO2 from escaping through the soil. The many natural CO2 seeping sites in Italy have no such safeguards. They are often remnants of ancient calderas where gas can freely escape from the soil into the atmosphere.

Peanut butter or a CCS below your lawn?

The lack of safeguards on the Italian sites is in fact so low that many of them are freely accessible for the public. Still the average risk of death from CO2 poisoning at such locations is just 1 in 280 million according to the research in the journal Proceedings of the National Academy of Sciences. As a comparison, the odds of dying from eating peanut butter are about 1 in 3300.

Still if someone were to give me the choice of either eating a peanut butter sandwich or building a CO2 storage facility under my lawn, I’d most certainly choose the former. Just as most people would judging from the many protests in Canada and Northern Europe where CCS plans were made.

Change of plans

As a matter of fact because of those protests most of the planned CCS facilities have either been cancelled or moved from populated areas, often to offshore facilities. This change of plans probably not only puts the public at rest, but according to the researchers CO2 seeps in wet environments pose an even smaller threat than those in dry areas.

Of course engineered underground gas storage would be much safer than the natural seeps in Italy. But if all fail-safes in such a facility would give, a situation comparable to the Italian seeps would arise.

Obviously the storage of CO2 to achieve emission reduction targets is a bit like cheating and as such is by no means an alternative to clean energy efforts. It can however help in reducing carbon emissions until the renewable energy sector has developed sufficiently.

© Jorn van Dooren | www.bitsofscience.org