Again Bio’s bacteria eats exhaust and spits vinegar (for the climate)

Again Bio says its modified bacteria currently eats about a ton of CO2 per day.

Spun out by researchers at the Technical University of Denmark, Again Bio sics its hungry microbes on flue gas from a wastewater treatment plant in Copenhagen. The startup is 2.5 years old, and it quietly raised a $10 million seed round in February from ACME Capital, GV (formerly Google Ventures) and Atlantic Labs. The company also benefits from the nearly $47 million grant (€43 million) that Horizon Europe awarded to a project using Again’s tech, PyroCO2.

Again’s whole thing is piping industrial exhaust into a 65-foot-tall bioreactor, where its bacteria feeds on climate pollution and hydrogen, and excretes a useful byproduct: vinegar. The startup says it refines that byproduct into acetic acid and acetate — base chemicals for stuff like detergents, paints, pharmaceuticals and textiles. The point-of-source carbon capture service that Again offers is free, because its business is to sell the output.

Image Credits: Again Bio

At the Copenhagen plant, Again says its fermentation vessel is currently operating in a sort of test mode, enabling the startup to give away samples of the resultant chemicals. However, co-founder and CEO Torbjørn Ølshøj Jensen told TechCrunch that Again has a contract with an undisclosed customer that is “large enough that our focus is really just on building plants and rolling them out.”

Jensen added that the tech is now “producing at yields that are commercially viable.”

The firm declined to say more about the deal, which is apparently driving its expansion in Europe and North America.

“It’s really dirty things we work with,” Again co-founder and COO Max Kufner told TechCrunch, “but the cool thing about these bacteria is they just feed off it […] and continue to develop themselves to cope with potential inhibitors present in the off-gas.”

In addition to genetically modifying the bacteria, “a lot of the work we’re also doing is forced evolution,” Kufner clarified.

Again aims to help decarbonize industrial facilities, but the startup relies on hydrogen made from fossil fuels to deliver energy to its specialized bacteria. According to Jensen, the startup’s chemical production can be “carbon neutral” using this gray hydrogen because Again can capture the CO2 from the hydrogen manufacturing process. Regardless, the methane industry, which powers gray hydrogen production, is a serious problem for the climate. Jensen added that Again intends to use green hydrogen — made via electrolyzers and renewable energy — in the future.