If we want to keep global warming below 1.5C, we can only emit another 500 gigatonnes of carbon into the atmosphere, according to the UN's climate council — that’s around eight years’ worth at the current rate.
In the race to cut emissions, a lot of hope is pinned on carbon capture and storage tech (CCS) — which captures the carbon produced in industrial processes before it reaches the atmosphere, be it in cement and steelmaking processes, oil refineries or natural gas production.
And investor interest in CCS is ramping up. UK startup Carbon Clean has just raised $150m — the largest round ever for a CCS startup, according to Dealroom.
Carbon Clean gets corporate backing from Samsung, Chevron and Saudi Aramco
There’s a lot of heated discussion about CCS’s relationship with fossil fuels, but big industry players are fervently backing the tech. Carbon Clean’s latest round was led by Chevron, and included participation from Samsung (which has a significant oil and gas portfolio) and Saudi Aramco, among others.
The round comes amid surging interest in CCS — last year, the global capacity of planned CCS projects grew 50% over nine months, and the industry was further boosted by the latest report by the Intergovernmental Panel on Climate Change (IPCC), which stressed the need for the technology.
Other forms of carbon removal are also attracting interest. Climeworks, a Swiss startup working on direct air capture (where carbon is removed from the air itself, rather than captured at source) raised a $650m round last month.
Driving the price down
“Point of source carbon capture is pretty simple,” Carbon Clean’s founder Aniruddha Sharma tells Sifted. “It’s not as complicated as direct air capture, and variations of it have been going on for about 50 years.”
CCS works by taking gases from the industrial process and moving them into a tower structure where they’re showered with a chemical that absorbs the carbon dioxide. It produces a beer-like substance with CO2 trapped within it, which is then heated to remove the CO2. That CO2 can then be used to make other products, such as fuels, or stored in abandoned gas wells.
Modelling suggests that the cost of storing CO2 emissions from natural gas plants is around $80 to $90 per tonne. To lower the cost of CCS, there’s been a drive to produce larger plants so economies of scale kick in and push the price per tonne down.
But that’s resulted in a problem: the initial cost of building a plant is high, and a lot of space is needed — Sharma estimates companies would need 40% more land per plant.
That’s where he says Carbon Clean’s tech comes in. It's managed to compress the size of the equipment needed and upped the efficiency by introducing a rotating disc into the tower, which increases the contact area for the reaction.
Sharma says its equipment needs 10 times less space than other models. “It means you don’t need to have ugly towers, you can have everything within a shipping container, and that makes adoption much, much easier. It opens up carbon capture for heavy industry.”
Carbon Clean says its tech brings down the cost to $45 per tonne, and that it can bring it down to $30 per tonne by 2025. CCS is also significantly cheaper than direct air capture removal — Climeworks is targeting $250 to $300 per tonne by 2030, for example.
Greening the fossil fuel industry?
There’s a lot of debate around where CCS should be deployed. Some experts stress that it should be used in sectors like cement and steelmaking, where emissions are unlikely to ever reach zero.
There’s an argument that its use in oil and gas production encourages the perpetuation of fossil fuels — because focus falls on making their processes greener rather than developing inherently more sustainable energy sources, like wind, solar and other renewables.
Some CCS projects have also fallen short of expectations. Chevron conceded last year that a CCS project in Australia had failed on its aim to capture 80% of CO2 emissions. The project did not involve Carbon Clean.
But other experts think removing any carbon from the atmosphere is positive. “I’ve got a carnivorous attitude to climate change,” says Jon Gibbins, a professor of CCS at Sheffield University and director of the UK’s CCS Research Centre. “We just need to stop the net addition of carbon dioxide to the atmosphere.
At the moment [oil companies] don’t have to [deal with Scope 3 emissions]. But regulation, or market differentiation or public opinion will force them to
“Oil companies will have to deal with their Scope 3 emissions eventually. They’ll have to sell oil and remove the corresponding CO2 from the atmosphere within that cost” — something he says they can afford, given the recent increase in oil prices.
“At the moment they don’t have to do it. But regulation, or market differentiation or public opinion will force them to. If we do have a way to remove the carbon we emit from the atmosphere and not dump it on future generations, the pressure for these companies to do it will get stronger and stronger.”
Sharma says Carbon Clean’s central focus is on helping the harder-to-abate industries.
“We focus on steel, cement, energy from waste, refining and petrochemicals. They’re industries you can't do away with in the short term or medium term, or in some cases the long term as well,” he says.
“It’s hard to find durable replacements, so our product is very much focused on industrial decarbonisation.”