We can have 10 times less carbon storage capacity than we thought

The world can lack storage space for carbon dioxide captured over the following two centuries, according to new research that suggests the practical capacity of the planet to hold the CO₂ Underground is much lower than what we thought.

The storage of carbon dioxide captured in underground tanks was presented by governments and industry as a means of reaching zero net without eliminating the use of fossil fuels.

The planet’s ability to store this CO₂ was considered vast, the estimates of the industry putting a global geological storage capacity at around 14,000 gigatons of CO₂. “Until today, storage capacity was, for all useful purposes, considered unlimited,” said Jeri Rogelj at the Imperial College in London, in the United Kingdom.

But with colleagues, Rogelj has carried out a more in -depth analysis of the storage reserves and found that the usable volume of storage space can be much smaller. The team analyzed stable geological training, excluding areas affected by risk factors such as the proximity of large cities, landscapes or regions sensitive to the environment vulnerable to earthquakes. Once these risk factors are taken into account, they conclude that only 1460 gigatons of geological storage capacity are available worldwide.

“According to a position where we have a practically unlimited storage potential, now CO₂ The storage potential on which we can count cautiously becomes a precious resource, “explains Rogelj.” We have reduced the practical potential that we think we should assume for Co₂ Storage by a factor of 10. “

Most climatic projections assume that certain levels of underground carbon storage will be necessary to allow the world to reach net zero emissions. The quantity of storage will be used largely depends on the extent to which the world manages to reduce the use of fossil fuels. If we continue to use geological storage to kidnap large volumes of emissions from fossil fuel factories Once the net zero has been reached, global carbon storage should run out of 2200, warn the researchers.

Rogelj maintains that its results mean that we should treat underground carbon storage sparingly, when all other decarbonise options have been exhausted. For example, rather than capturing emissions from coal or gas power stations and storing them underground, savings should rely on zero emission energy sources when possible, he says.

Which would release the underground storage capacity for CO₂ trapped using technologies such as direct air capture (DAC), which derives excess CO₂ directly from the atmosphere. The DAC, as well as other so-called “negative emissions” technologies, could offer the world a path to go beyond zero-clear emissions and provide negative net emissions, effectively reversing climate change.

If the 1460 Gigatonnes of achievable underground co₂ The storage capacity was reserved for this CO₂ Samples, the world could reverse up to 0.7 ° C of warming, Rogelj and his colleagues calculate.

However, Stuart Haszeldine at the University of Edinburgh in the United Kingdom warns that if the usable capacity for geological storage is likely to be lower than industry estimates of 14,000 gigatons, it suspects that the new lower figure is too conservative.

The approach of the risk factors team is “extremely prudent”, he argues, stressing that certain areas subject to earthquakes, such as the North Sea, are actually excluded by their approach but can always be safe places to sequester carbon. “We know enough about carbon storage and oil reserves to know that if you have a field of oil or gas or carbon dioxide, you can have an earthquake of magnitude 6 and it shakes it, but nothing happens,” explains Haszeldine.

Haszeldine points out that most analysts and researchers assume that carbon sequestration will be used to help the world move away from fossil fuels. This means that the volume of carbon injected underground each year should decrease once the world has reached clear zero emissions, he says.

“”[Carbon capture and storage] Has never really been considered the final point, the final solution, for everything, for all our pessimism and the ailments of climate change, “explains Haszeldine.” It is really considered a set of transition of actions, where this transition could last 30, or 50, even 150 years, to pass from oil and gas. For this reason, you do not need really astronomical quantities of CO₂ Storage capacity. “”