WATCH: Direct air capture (DAC) is widely seen as an answer to lowering the planets level of carbon dioxide (CO2) - one of the bullets in the decarbonisation gun.
The Intergovernmental Panel on Climate Change (IPCC) claim that we need to limit global temperature rise to 1.5°C above pre-industrial levels. This not only requires the emissions of greenhouse houses to be reduced significantly, but will also, “rely on large-scale deployment of carbon dioxide removal (CDR) measures.”
CDR measures can include afforestation, carbon farming, wetland restoration, and direct air capture.
Direct air capture is the practice of capturing CO2 directly from the atmosphere. The CO2 can then be utilised in low carbon products, or permanently sequestered, and achieving negative emissions.
According to the International Energy Agency (IEA), there are currently 19 DAC plants in operation worldwide and capturing more than 0.01 metric tonnes of CO2 per year.
Back in September 2021, Swiss company, Climeworks, brought online the latest in the 15 strong DAC facility portfolio.
Named Orca, the plant is able to capture 4,000 tonnes of CO2 per year, the equivalent of ~870 cars.
At launch, Orca was – and still remains, the world’s largest DAC facility.
Describing the plant, Christoph Beuttler, Head of Climate Policy at Climeworks, said, “Orca is our second-generation technologies. Over it’s lifetime, per tonne captured, it needs about 50% less resources - so steel, etc. Per capita unit it also captures a lot more CO2.”
“It’s the technology we will base our next plant that that adds one order of magnitude - that that will be based on the same technology. So this is quite significant. We would describe it as a first of a kind commercial demonstration.”
All CO2 captured from the Orca plant will be permanently sequestered underground by Icelandic company, Carbfix.
Kári Helgason, Head of Research and Innovation at Carbfix explained, “[We are] dedicated to capturing and injecting CO2 into the subsurface and turning it into stone where it remains for millennia and therefore taking it off the short carbon cycle.”
“This is really nature’s way of storing carbon. The technology is simply accelerating nature’s way of storing carbon in rocks. And they are naturally stored in rocks just as [in] vegetation and trees.”
Another company removing CO2 from the air using direct air capture is Carbon Engineering.
Currently, Carbon Engineering operate their pilot plant in Squamish, British Columbia, where it was been running since 2015 and purifying ~1 tonne of CO2 every day.
The Canadian company are currently developing a number of facilities, including their first commercial facility, based in the Permian Basin, that will capture 1 million tonnes of CO2 per year. And another targeted for North-East Scotland that will remove between 500,00 and 1 million tonnes of CO2 per year. Combined, this is the equivalent of planting 80 million trees, or taking 500,000 cars off the road.
Discussing the UK facility, Amy Ruddock, Vice President of Europe for Carbon Engineering, said, “[We’re in] the first stage of detailed engineering on this project and it’s a significant milestone in progressing the project.
“I think it’s a great milestone for the UK – the first direct air capture plant in the U.K., which enables us to start building that knowledge, building those local supply chains. But also, when you look globally, it’s one of the first megaton scale projects out there in direct air capture in the world.”
“This project in the UK means that there is this leadership opportunity for the UK as well.”
Carbon Engineering and their partners, Storegga, hope to have the plant operational by 2026.
But where else can carbon dioxide, captured through direct air capture, be utilised?
The most controversial utilisation is enhanced oil recovery (EOR). This is the practice of pumping CO2 into depleted oil reservoirs to help extract more oil the otherwise possible.
Some in the industry, such as Ruddock, believe this to be a necessity to allow DAC companies to still turn a profit saying, “In EOR the source of carbon dioxide to do it, is fossil fuel source. So replacing that with direct captured CO2 significantly reduces the footprint of the oil.”
“I’d also say that when you look at this climate problem - what’s very clear is that you need to get the costs down for direct air capture. How do you get the cost down? Well, a lot of it is about deployment and learning.”
“There is no revenue model today for clearing up carbon dioxide from the sky, so you need to start to think about how can you deploy today.”
“And sometimes that can mean that you need a commodity value of the carbon dioxide.”
“I think you should think about EOR utilisation is as early use cases of deploying this [DAC] technology.”
Climeworks however disagree. When asked about Climeworks’ stance on EOR and if it’s a responsible use of direct air captured carbon, Beuttler stated, “We have a very simple position here. We won’t engage - full stop.”
“There are discussions that it might be net removing, if you look at the whole value chain, but we think that if your mission is to save the planet from global warming, you shouldn’t contribute to producing more oil.”
Another utilisation for captured carbon is to produce synthetic fuel by combining the CO2 with hydrogen.
The transport industry is responsible for one fifth of global carbon emissions and parts of the industry still remain particularly difficult to decarbonise - such as aviation.
Synthetic fuels is one of the tools that can be used to help in this fight against decarbonisation, allowing a net zero product to be made and used.
Nancy Young, Vice President of Environmental Affairs at Airlines for America, who represent the major US airlines and Air Canada, believes we need to look at direct air capture as a source of producing a synthetic fuel for years to come saying, “We are very committed to reaching net zero carbon emissions by 2050.”
“In fact, that’s a commitment across our membership as US airlines. Now, in fact, some of our members are committing to do that even earlier.”
“So we really do hope to go from our current two percent of the US greenhouse gas emissions inventory to get that down to be zero by 2050.”
“Each of them [our associate members] are engaging in sustainable aviation fuel purchases and increasingly looking towards the future when direct air capture would be available for that.”
“Right now, it’s largely a biomass, circular carbon dioxide economy. But if we can grab it from the air instead of using it out of biomass, that solves two problems.”
“It becomes circular to the fuel that we use, taking it out of the air. But it also then addresses our fuel needs at the same time.”
For more on each of the mentioned companies, direct air capture technology, the affordability of DAC, the (lack of) policy that is holding it back, the challenges DAC companies are facing and the future watch Direct air capture | Removing CO2 from the atmosphere here.