What is carbon capture and storage?
- Carbon capture and storage (CCS) is a way to catch carbon and trap it beneath the earth. It is different to carbon dioxide removal (CDR) — where carbon is sucked out of the atmosphere — although some of the technologies overlap. The key difference is that CDR brings down the level of carbon dioxide in the atmosphere, cooling the planet, while CCS in fossil fuel plants and factories prevents the gas from getting out in the first place.
- In its latest review of scientific research, the Intergovernmental Panel on Climate Change (IPCC) found both options will be needed for emissions that are hard to wipe out. For chemical processes that release carbon dioxide, there are few alternatives to capturing CO2 straight away or sucking it out of the air later. Scientists see a big role for CCS in factories that make cement and fertiliser, as well as in plants that burn rubbish. They are split on whether it makes sense to use it to make steel and hydrogen, which have some greener alternatives.
- Most of their skepticism goes to capturing carbon when making electricity, because there are already cheaper alternatives that work better, like wind turbines and solar panels. In theory, it could play a role in gas plants as a back-up when the sun doesn’t shine and wind doesn’t blow — particularly in countries that are still building fossil fuel plants today — but it would have to quickly grow cheaper and more effective.
How well does CCS work?
- For decades, engineers have captured carbon from concentrated streams of gas — pushing it into tanks, scrubbing it clean and using it in industry or storing it underground. Some bioethanol plants, where the gas stream is pure, already report capturing more than 95% of the carbon emissions.
- But when it comes to capturing carbon from dirtier gas streams, like those from factories and power plants, CCS projects have repeatedly overpromised and under delivered. We need to use some kind of chemical to grab that CO2 from everything else.
- While a handful of test facilities have managed to capture more than 90% of emissions from some dirty gas streams, commercial projects have been plagued with problems. Some have broken down or not been made to run all the time. Others have been designed to capture only a fraction of the total emissions.
- Experts see the failures of CCS more as an economic problem than a technical one. They say companies have little incentive to capture their pollution. This is existing engineering — but we have to start spending money, building things and breaking them until they work.
Why is CCS controversial?
- Activists have called out energy companies for failing to capture much carbon while at the same time drilling for oil and lobbying against laws to cut fossil fuel production. They have pushed policymakers to put more weight on societal shifts — like cutting energy demand — rather than placing their faith in shaky technologies.
- The danger is not just that the technology does not seem to work as advertised. CCS also gives companies fighting to burn fossil fuels access to policymakers and a “social license to operate. They’re not using carbon capture as a climate solution. They’re using it to actually enhance extraction.
- A big part of this is what fossil fuel companies call enhanced oil recovery — pumping carbon dioxide underground to push out more oil from drying wells. Historically, most captured carbon has been used for this purpose.
- Scientists have also questioned how serious the industry is about its commitments. After decades of pushing the technology, there are only 30 working CCS facilities, according to industry data from last year, with 11 being built and 150 in planning. A study in 2020 found more than 100 of the 149 CCS projects planned to be operational by 2020 have been scrapped or placed on indefinite hold.
How can CCS work better?
- Experts say momentum to capture carbon is starting to pick up.
- In Norway, German industrial giant Heidelberg Materials is building the first facility to capture carbon from cement and store it underground. The company claims a capture rate of close to 100% is possible. Still, it only plans to capture half of the emissions from the site.
- This was done to get the facility built as fast as possible and showcase the technology. They designed the project around the available waste heat that we have on site, so they wouldn’t get the additional dimension of having to add extra energy from the power grid.
- Oil and gas companies are also starting to weaken their grip on the CCS industry. According to the International Energy Agency (IEA), a Paris-based organization led by the energy ministers of mostly rich countries, new companies are focusing on specific parts of the problem like transport and storage.
- There’s now a bigger focus on storing CO2 than using it to extract more oil and to look at dedicated storage.
- To make the technology grow cheaper and work better, analysts say governments need to tax carbon, make it easier to approve CCS projects, and help set up the infrastructure around it. They are less sure about subsidizing the technology itself.
- Source: Indian Express
