The Intergovernmental Panel on Climate Change (IPCC) released a report this week outlining the drastic changes society needs to endure if we are to limit global warming to 1.5 degrees Celsius above pre-industrial levels. According to the report, we have about 12 years to undergo these changes and prevent the worst effects of climate change, such as extreme weather events, rising sea levels, and food shortages.
One proposed method to expand this timeline is Direct Air Capture (DAC), the process of removing carbon dioxide (a large contributor to climate change) from the atmosphere. With DAC, air is filtered through a non-hazardous chemical absorbent that captures about 80% of the air’s carbon dioxide content. The chemical substance drops to the bottom, while the cleaner air is released.
The collected CO2 then goes through a series of purifying processes, eventually producing a pure version that can be stored underground, turned into a carbon-based product, or—as clean energy company Carbon Engineering suggests—synthesized into cleaner transportation fuels.
Purified carbon dioxide fuel would create a circular system of emissions: your car runs on fuel made from the air’s CO2 (emitting CO2 back into the air), and a facility captures this CO2 again to make more fuel.
“So the net CO2 emission is zero,” Steve Oldham, CEO of Carbon Engineering, told Fortune. “It’s all working, we’ve made fuel. The next step for us to is scale up.”
A fourth option for disposing of collected carbon dioxide is enhanced oil recovery, or using atmospheric carbon in the oil drilling process. Oil drilling already uses CO2, but using a purified version from the atmosphere buries the carbon dioxide below ground, while also supporting oil-based economies.
“It’s a way that you can continue to generate oil, while our dependence on oil remains as a society, but at the same time you can do negative emissions,” said Oldham.
Critics of DAC argue that the number of facilities necessary to make a valuable impact is impossibly high; plus, the idea of CO2 removal gives policymakers an excuse not to purse emission reduction as fervently. Oldham, however, argues that there’s not enough time to be rejecting any aid to climate change prevention when that 1.5 degree-limit is so near.
“There’s no plan C here,” he said. “The scale of the problem is so large you can’t just select one solution and simply use that.”
Carbon Engineering, while still raising financing to get their ideas to the market, has been running its pilot plant in Squamish, British Columbia since 2015. Other companies, like the Zurich-based Climeworks, have also developed DAC facilities around the world.