Making fuel from the air

Local company wants to change CO2 into energy

Air capture the practice of turning air into gas might seem as improbable as turning lead into gold. But unlike conventional alchemy this transformation has a basis in fact — and the potential to create an equally valuable substance while helping the environment.

The idea of air capture in which a variety of methods can be used to separate carbon from ambient air has been around since the 1970s. But it became a reality last month when British company Air Fuel Synthesis produced five litres of gas from air and water. Air Fuel Synthesis may have beaten Calgary company Carbon Engineering to the punch but Mike Crabtree the company’s chief corporate and business development officer is still happy with their rival’s accomplishment hailing their approach as “innovative.”

“There is plenty of room in the environmental industry for a number of different technologies. Rather than us not liking to see any competitors out there we laud the fact there are competitors out there.”

Indeed Carbon Engineering is just one of several North American companies working in the field. It grew out of research conducted by University of Calgary professor David Keith whose team built a prototype for air capture in 2008. Funded by angel investors including Bill Gates and Murray Edwards Carbon Engineering launched the following year.

“The most challenging part of it and exciting part of it” says Keith “are running a startup and getting people to come together with talents and money and energy to actually try and build something that matters.”

The company’s pilot plant is scheduled to be in place next year and operating by the end of the decade says Crabtree with industrial-scale plants built to capture one million tons of CO2 a year slated to follow. Carbon Engineering employs the “wet scrubbing” method of carbon capture which extracts the gas through an air contactor using a water-based-solution. This is followed by a chemical regeneration process similar to that used to produce kraft pulp in the paper industry which creates particles often out of limestone that are then heated in a kiln.

The pure CO2 generated can then be used in several possible ways including pumped into greenhouses or algae beds or buried underground. It can also be used to make hydrocarbon fuels which are carbon neutral if renewable energy is used and cleaner burning than conventional gasoline (Carbon Engineering currently uses natural gas although it’s reportedly investigating alternatives such as solar thermal).

While the potential to capture emissions from industrial sources is obviously beneficial Crabtree notes the technology also offers the opportunity to actually reduce CO2 concentration in the atmosphere much like trees and shrubs.

“You’ve heard of a number of technologies that prevent CO2 emission” he says. “This actually removes it from the air.”

If all this sounds too good to be true even Carbon Engineering acknowledges the technology has drawbacks. It will always be more expensive and difficult than conventional energy production although rising oil prices could reduce this disadvantage.

The company also warns of the “moral hazard” air capture poses — distracting attention from other necessary means of reducing carbon emissions. Crabtree estimates it will likely be another 20 to 25 years before the technology is widely available commercially.

Time will tell if air capture really is a viable technology. But an emissions-free fuel source that uses a readily available limitless substance might be a miracle even greater than alchemy.