Carbon dioxide-to-chemical start-up Again raises $43 million

The synthetic biology start-up Again has raised $43 million in a series A funding round led by GV, formerly Google Ventures. Again is commercializing a fermentation process that uses genetically engineered microbes to make acetic acid and derivatives from carbon dioxide and hydrogen.

Again launched in 2021 based on research conducted at the Technical University of Denmark, Stanford, and the Massachusetts Institute of Technology. Last fall, the firm started up a pilot plant at a wastewater treatment facility in Copenhagen. The system takes the methane-rich gas stream from an anerobic digester, converts the CH₄ to H₂ and CO₂, and feeds that mix into a bioreactor with an output capacity of roughly 5,000 metric tons (t) per year.

The firm says the resulting acetate chemicals are suitable for use in adhesives, solvents, plastics, textiles, and cosmetics and have a carbon footprint one-fifth the size of the conventional petrochemical route. The chemical distributor Helm will take Again’s output to market under a 10-year deal the firms signed in February.

The company has competition from firms looking to make use of electron-rich waste gas streams and from others converting CO₂into chemicals. To name just two, LanzaTech is building multiple plants that will make alcohols from industrial carbon monoxide byproduct streams, which are normally incinerated as waste. And Air Company, one of C&EN’s 10 Start-Ups to Watch in 2022, is preparing for a commercial-scale plant that will catalytically convert CO₂ and H₂ into jet fuel, methanol, and ethanol.

Again cofounder Max Kufner says the ability of the firm’s technology to handle impure waste streams as a feedstock helps it stand out to investors. For the next installations, he says, the firm is in talks with chemical manufacturers, oil refineries, and other large industrial CO₂ emitters. It is also working with Arkema, Johnson Matthey, DSM-Firmenich, and others on a $47 million demonstration project to turn 9,100 t per year of CO₂ into 4,000 t of acetone at an industrial park in southern Norway.

Getting access to more than $100 million in capital less than 3 years after launch is impressive, says James Iademarco, founder and CEO of the chemistry and biotech consulting firm Strategic Avalanche. “They’ve convinced investors they have something special.”

Again doesn’t publicly disclose many technical details, but the firm has two recent patents on enhancing the growth of the CO₂-fixing bacteria Moorella thermoacetica and Moorella thermoautotrophica through gene editing and mineral supplementation. “If improved microbial growth rates is a piece of their ‘special sauce,’ that can contribute to lower cost of production at scale,” Iademarco says.

Still, Iademarco is cautious. The field that Again is entering has “a lot of dead bodies,” he says. Even when the biochemistry works, feedstock woes and product purification have vexed previous biobased chemical projects.

For example, efforts to make ethanol from agricultural waste have swallowed about $3.5 billion in investment in the US alone, he says, “and there’s really not a drop of cellulosic ethanol to show from those commercial assets.” And multiple start-ups have stumbled trying to upgrade waste into fuels and chemicals, including Fulcrum BioEnergy, which recently shut down its flagship plant near Reno, Nevada, and abruptly disappeared from the internet.

At the same time, the business environment for biobased and low-carbon chemicals is a lot better than it was 10 years ago, Iademarco says, and start-ups can learn a lot by studying past successes and failures. Taking waste gas containing CO₂ and converting it to a higher-value chemical is a worthwhile pursuit, he says. “I’m not one of those people that says, ‘Hey, that’s been tried before. You’re wasting your time.’ I’m a strong believer in this space.”