Here's Cheers to a New Use for Co2 from the Atmosphere

It won't tackle global carbon emissions yet, but a new technology from Australia’s national science agency, CSIRO, has found a way to pull carbon dioxide (CO₂) out of the atmosphere and put it into beer and other beverages.

At a time when CO₂ levels in the atmosphere are increasing, there have been shortages in industrial supplies of the gas over the past decade, impacting on fizzy beverage supply and food production.

CO₂ is in global demand for purposes ranging from making fizzy beverages to food packaging and controlling the atmosphere in agricultural greenhouses.  

The new technology is called Airthena, and was developed in partnership with Monash University, Energy Infrastructure and Resources and H2H Energy.

It draws on recent breakthroughs in advanced filtration methods to solve challenges around the water-food-energy nexus including sustainable resources, and environmental value and resilience.

Airthena captures CO₂ directly from the air using tiny sponges known as metal-organic frameworks (MOFs), and can be scaled up for commercial production.  

CSIRO project lead, Aaron Thornton, said the solution had broad applications across a wide range of industries.

"As it requires just air and electricity to work, Airthena offers a cost-effective, efficient, and environmentally-friendly option to recycle CO₂ for use on-site, on-demand," Dr Thornton said.

"It also provides a more reliable source of CO₂ for use in small-scale applications ranging from beverage carbonation to controlling pH in swimming pools, and industrial cleaning."

A common method companies currently use to generate CO₂ onsite relies on burning natural gas, which is subject to market price and supply fluctuations.

CO₂ can also be bought from a supplier, which can involve expensive long-distance transportation and be prone to shortages.

Airthena only needs about two kilowatt-hours of electricity per kilogram of CO₂, equal to around 20 cents per kilogram at minimum solar energy prices of $0.1 per kilowatt-hour at its current scale.

Jon Murphy is General Manager of Murphyfresh Hydroponics, which uses CO₂ in their greenhouses to grow tomatoes and other produce.

"We spend a lot of money on buying in carbon dioxide, so we're eager to see a new technology that can deliver CO² on-site, on-demand," Mr Murphy said.  

Airthena is capable of capturing two tonnes of CO₂ from the atmosphere a year, making it suitable for small-scale applications right now, but Dr Thornton says it is scalable.

While Airthena won’t make any immediate impact on cutting global CO₂ emissions due to its scale, it will help businesses with a more reliable source of the gas for their everyday operations, while reducing their carbon footprint.

"We are now exploring options for taking Airthena to market, which include reducing the cost of the unit for small scale applications and having it tested to ensure it meets food quality standards, or working with the food production industry to scale up the technology for larger applications," Dr Thornton said.

Airthena could also be valuable for the chemicals industry which use CO₂ as a feedstock for making other compounds and materials such as methanol and methane.

The collaboration and development of Airthena was supported by $725,000 from the Science and Industry Endowment Fund.