Storing billions of tonnes of CO2 underground would be a “safe and effective” way to help limit the effects of climate change, a new study says.

 

The research suggests that large amounts of CO2 could be stored under the ground or sea with only a small risk of surface leakage in the following 10,000 years. However, if CO2 storage is poorly managed, higher amounts of leakage can be expected.

The findings help dispel common “misconceptions” about the dangers associated with CO2 storage.

 

by Daisy Dunne, Carbon Brief

This text is a section taken from the full article Carbon Brief, June 12, 2018.

Article Intro

Carbon capture and storage (CCS) is a process whereby CO2 is “captured” before it enters the air and is then transported to a storage site – which could be, for example, a depleted oil or gas field or a deep rock reservoir beneath the sea.

Though the technology is currently restricted to pilot projects, many view its large-scale development as an essential step to limiting the effects of future climate change. For example, the Aquistore Project is the most comprehensive full-scale geological field laboratory for CO2 storage in the world.

In its most recent assessment report, the Intergovernmental Panel on Climate Change (IPCC) concluded that avoiding dangerous climate change would cost twice as much without CCS.

One barrier to the development of CCS has been the costs associated with directly capturing CO2. Another barrier is an unfounded fear that, once underground, stored CO2 may leak out into the atmosphere.

It is this second barrier that is addressed by the new research, which is published in Nature Communications.

To address the question of leakage, the researchers developed a new model – known as the Storage Security Calculator – which looks at what would happen if 12bn tonnes of CO2 were injected under the ground and left for 10,000 years. The 12bn-tonne target reflects the EU’s ambition for CO2 storage by 2050.

The findings suggest that – providing a suitable storage site is chosen – the risk of CO2 leakage would be minimal, says lead author Dr Juan Alcalde, a geologist at the University of Aberdeen. 

Article Conclusion

The new study “puts to rest fears about CO2 storage”, says Prof Martin Blunt, chair in petroleum engineering at Imperial College London, who was not involved in the research. He tells Carbon Brief:

“It’s an important study because it helps deal with common misconceptions regulators, the public and scientists not working in the field have with CO2 storage.

“CO2 storage is not like nuclear waste, which will corrode and eventually leak out of anything it’s stored in. Unlike nuclear waste, CO2 becomes safer and more secure the longer it stays in the ground due to a range of physical processes, such as mineralisation.”

Read the full article on Carbon Brief, here.