Cheap one Air

Aspirating carbondioxide from the air is less expensive than researchers thought.

The extraction of CO2 from the earth's atmosphere could be more than an costly way of avoiding climatic disasters. Joule's Joule report was authored by research scientists at Calgary, Canada-based Carbon Engineering, which has been running a CO2 extraction facility in British Columbia since 2015. This facility - built on a design named AirCapture - formed the foundation for the business case that included estimated costs from all key component suppliers.

The costs of extracting one ton of CO2 from the atmosphere range between USD 94 and 232, dependent on a multitude of possible designs and economical hypotheses. Last extensive research of the American Physical Society's 2011 study of the technique estimates that it would be $600 per ton. It says Carbon Engineering has released the document to drive discussion about the costs and potentials of the technique.

"We' re really trying to seriously commercialise DD, and to do that you have to have everyone in the supply chains on board," says David Keith, senior researcher at Carbon Engineering and carbon physics at Harvard University in Cambridge, Massachusetts. Carbon Engineering was established in 2009 and is one of the few businesses that deals with separation technology.

Last year, a rival, Climate Works in Zurich, Switzerland, opened a commercially viable plant that can remove 900 tons of CO2 a year from the air for use in glasshouses. ClimateWorks has also opened a second plant in Iceland that can separate 50 tons of CO2 per year and burry it in subterranean rock outcrops.

In Climeworks' opinion, the capture of one ton of CO2 in his factory in Switzerland is worth about 600 dollars. Corporate officers anticipate that in 5-10 years, the number will fall below $100 per ton as the operation increases. Meanwhile, Carbon Engineering's carbon engineering papers offer the most comprehensive view of the total investment required for such a process.

The Carbon Engineering Department is also credited by Pacala with the publication of its results. The Carbon Engineering designs blow air through turrets containing a mixture of caustic soda that combines with CO2 to create caustic soda. According to Keith, the firm can manufacture them at a price of about one dollar per liter. As Carbon Engineering was configuring the air separation system for this application, the unit was able to reduce operating expenses to up to $94 per ton of CO2.

Lackner, a forerunner in this area, who leads the Center for Negative Emission at Arizona State University in Tempe, says carbon engineering has taken a brutal drive to reduce cost with known technology. Under the assumption that CO2 will be bury to compensate for carbon dioxide emission, a $100 per ton bill would increase about $0.22 cent to the cost of one liter of petrol, Lackner says.

This is a significant but not unparalleled rise in prices, he added. Ultimately, the economic viability of CO2 capture depends on a number of variables that differ from site to site, such as the electricity prices and whether a business has or has not been granted public subsidy. However, the costs per metric ton are likely to continue to be higher than the commercial prices of carbons for the time being.

For example, in the European Union's emissions Trading System, emission allowances are traded at around 16 (US$19) per ton of CO2. However, CO2 extraction technologies could enter those countries where CO2 can be bought at a bonus or transformed into a useful commodity such as petrol. Meanwhile, in the United States, Climate Engineering is reviewing a recently extended CO2 separation and storage grant that could include a $35 per metric ton US federal income tax benefit for CO2 from the atmosphere transformed into motor oil.

California regulatory authorities are discussing a move that would allow such fuel to be eligible for the state's Low Climate Fuel Standard, which currently trades at around $135 per metric ton in emission allowances.