A pioneering ‘fingerprint’ test that hopes to build confidence in the geological storage of carbon dioxide (CO2) has been used for the first time in Canada.

The test, initially developed by researchers from Scottish Carbon Capture and Storage (SCCS), checks for leaks from carbon capture and storage (CCS) sites where man-made CO2 emissions are stored deep underground.

The technique has been used for the first time in Canada where it was conclusively used to investigate an alleged leak from CO2 underground at a farm in Saskatchewan.

The test concluded that the high levels of CO2 recorded on the farm arose from nearby wetlands – not as a leak from a nearby CCS site at Weyburn Oil Field.

SCCS scientists developed the method to measure tiny traces of the inactive natural gases, or noble gases, that are found in CO2. These noble gases vary depending on whether the CO2 is from just below the ground or deeper, thus enabling scientists to ‘fingerprint’ a sample and pinpoint its source.

“Our method of identifying any leaks should give assurance to local communities”

Dr. Stuart Gilfillian, study leader

This new test will bring reassurance and allows scientists and storage site developers to assure residents that CO2 storage sites are secure, useful in countries such as Canada and the US where onshore CO2 storage is already underway.

Dr. Stuart Gilfillan of the University of Edinburgh’s School of GeoSciences and leader of the study commented, “CCS is an essential means to curb emissions of greenhouse gases, which is needed to limit global warming to 2°C as internationally agreed in Paris.”

“Securely storing captured CO2 is critical to its success and our method of identifying any leaks should give assurance to local communities.”

SCCS first discovered that CO2 from industrial sources and naturally occurring CO2 both have distinctive chemical fingerprints in July 2016. The natural fingerprint of captured CO2 varies on the fuel producing the gas, such as coal, oil, natural gas or biomass, and the technology used to capture it.