Climate crisis: a return to carbon dioxide capture and storage technology? | tagesschau.de

It’s been controversial for a long time, but given the climate crisis, storing carbon dioxide in the Earth could be celebrating a renaissance. How safe is the technology? And can it really contribute to protecting the climate?

By Marilyn Wegmann, tagesschau.de

Germany has committed: the country must be climate-neutral by 2045. But no Emissions aren’t falling fast enoughto achieve this goal. So the researchers call for CO2 reduction in other ways in addition to the savings. In Germany, a well-known technology could mark a comeback: carbon capture and storage (CCS), in German: separating carbon dioxide and storing it underground.

A trip to Norway by Minister for Economics and Climate Protection Robert Habeck two weeks ago may be an indication of this. Because carbon dioxide from Germany will be transported to Norway in the future and stored there under the sea floor. Before the end of this year, the federal government intends to develop a carbon management strategy and remove legal obstacles that currently prevent the transport of carbon dioxide to Norway.

Use of old natural gas fields

With carbon capture and storage, carbon dioxide from coal-fired power plants or cement plants, for example, is separated, liquefied and then transported to a storage site via pipeline, ship or truck. This can be in deep rock layers on land (onshore) or under the sea floor (offshore). Ancient natural gas fields are also used to introduce carbon dioxide, as the gases have already been stored here for at least 10,000 years.

Carbon dioxide capture is currently pursued mainly in industrial companies. There are different methods starting at different stages of the industrial process. They either remove carbon dioxide before or after industrial processing or treat air used for combustion.

Filtering it out of the atmosphere is currently still very expensive and energy-intensive. According to Hapc, carbon dioxide capture and storage should be a temporary solution to currently unavoidable emissions.

Unavoidable emissions in cement production

“Coal-fired power plants are no longer a problem when it comes to CO2 separation,” says Bernd Ebel, head of the Department of Energy Systems and Technology at the Technical University of Darmstadt. Because they no longer have a future – and investments in technology with an expiration date are not economically viable.

It’s different in the cement business, for example. Carbon dioxide is inevitably produced there and concrete will remain a popular building material. According to one of them, production creates WWF report From 2019 a total of eight percent of all greenhouse gas emissions worldwide.

There is no industrial use in Germany

However, in the long term, carbon dioxide should not only be exported, but also stored in Germany. Possible places for this already exist: in the deep rock layers of the German North Sea, according to A Federal Institute for Geosciences and Natural Resources (BGR) Space for a few billion tons of carbon dioxide. However, they are rarely used today.

Because more than ten years ago there was already a heated debate about carbon dioxide storage in Germany. At the time, coal-fired power plants in particular wanted to give themselves a greener coat of paint. Citizens’ initiatives have taken action against this. As a result, there is no industrial use of CCS in Germany and only a few research projects.

Geologists believe the technology is safe

But even today, when it is no longer a matter of life cycle assessment of coal-fired power plants, there is still criticism about CCS. Carsten Smid is a climate and energy expert at Greenpeace. Even after ten years, CCS is not an option for him. Instead, he fears that the carbon dioxide could escape back through leaks and earthquakes.

Klaus Wallmann sees it differently. He has been researching carbon dioxide capture and storage at the GEOMAR Helmholtz Center for Ocean Research in Kiel for years and is of the opinion: “We need carbon dioxide capture and storage to limit climate change.” Many of his colleagues described it the same way. Carbon Dioxide Capture and Storage is a way to become climate neutral. This means that the amount of emissions emitted and removed is balanced. This can happen, for example, through reforestation or through technologies such as carbon dioxide capture and storage. Moreover Intergovernmental Panel on Climate Change It therefore includes carbon dioxide capture and storage as a way to combat climate change.

If leaks occur, they have minimal impact on the ecosystem

Wallmann was also the coordinator of the EU funded project ECO2. A team of scientists has checked Norwegian carbon dioxide storage sites for leaks — and they haven’t found any. If the gas does escape however, the effect on living organisms will be minimal, according to Wallmann. “If carbon dioxide escapes from a spill, it dissolves near the bottom. Then the water becomes acidic, and that has a negative effect on biodiversity. However, the radius of damage is small.”

Sebastian Bauer is a geologist at Keele University and on the project gustor concerned. Among other things, the team wants to recalculate the geological storage capacity for carbon dioxide under the North Sea. Bauer actually did extensive research on carbon dioxide capture and storage ten years ago. He also believes that ambitious climate targets cannot be achieved without carbon dioxide capture and storage. “But that was the case 15 years ago.” According to Bauer, the potential risks are closely related to the respective location of CO2 storage.

Test site in Kitzen – 67,000 tons of carbon dioxide injected

In the case of potential CCS sites, the selection of suitable sites is particularly important. With carbon dioxide stored in rock layers deep underground, there are more assets protected – such as buildings and groundwater. The latter in particular can be polluted when carbon dioxide is injected into the ground.

A pilot project has shown that storing carbon dioxide on the beach can still work kezin. Between 2008 and 2013, scientists from the German Research Center for Geosciences (GFZ) in Potsdam injected about 67,000 tons of carbon dioxide into the Earth. Subsequent monitoring took place over a period of four years. Since then it has been considered as one of the pioneering CO2 storage projects.

The primary objective: to avoid emissions

If Habeck has his way, Germany will soon be pumping some of its CO2 into Norway. The Minister for Economics considers that the use of carbon dioxide capture and storage is necessary so that Germany can achieve the goal of climate neutrality by 2045. This is also underlined evaluation report The carbon dioxide storage law, which also regulates carbon dioxide capture and storage. However, the ultimate goal is still to reduce emissions.