Former oil wells could be turned into CO2 burial test sites

A project to test if abandoned oil and gas wells could be used to bury carbon dioxide underground will begin next year.

A group of universities and fossil fuel companies have announced they have identified 20 potential sites across Britain which could be used to research carbon capture and storage (CCS), The Guardian has reported.

The Net Zero RISE (Research Infrastructure for Subsurface Energy) scheme is a collaboration between the Universities of Newcastle, Oxford and Durham, as well as the energy firms IGas and Third Energy.

CCS involves compressing carbon dioxide emissions into a liquid before pumping them underground where they cannot cause any more global warming.

Although it is intensely controversial as it would permit continued burning of fossil fuels into the future, many scientists and experts believe CCS will play a part in mitigating against climate change.

Many hope exhausted fuel reservoirs under the North Sea are the UK’s best bet for large-scale CCS, but the Net Zero RISE team argue the technology can be easily tested in empty onshore oil and gas wells first.

“CO2 storage in the North Sea is probably going to be very important, but we need an onshore capability, a national asset, so we can do testing and look at what monitoring is adequate to understand where the CO2 has gone,” Professor Richard Davies from University of Newcastle, the head of the project, told The Guardian.

“If we don’t do this soon, we will lose an opportunity to use this infrastructure,” he said, noting empty wells are normally quickly filled with cement.

“These assets are already there, while drilling [new] boreholes is very expensive and adds a certain amount of risk. The range of boreholes we have will also give opportunities to test different rock types.”

The team also intend to explore using old oil and gas wells to store hydrogen, which could also play a part in a future net zero energy mix.

According to the government’s own net zero strategy, Britain will need to be capturing and safely storing about 50m tonnes of CO2 by the mid 2030s, while by 2050 CCS will have to ramp up to around 95m tonnes.

As well as successfully pumping emissions into storage facilities underground, scientists also need to test how to monitor CCS sites to ensure the carbon is not leaking out back into the atmosphere.

Although CCS has been successfully put into practice at around 20 large-scale projects around the world, it remains a new technology and for now fairly expensive also.

However, the International Energy Agency reports 30 more projects are currently in development and if CCS comes to fruition as policymakers hope it could reduce global emissions by a fifth.