Copper is crucial to the energy transition away from fossil fuels. The metal is an excellent conductor of electricity, used in everything from electric vehicles to wind turbines. But by the end of the decade, the International Energy Agency expects copper supplies to fall 20% short of demand.

A stealthy startup thinks it can close the gap by helping miners extract more copper from their mines. To do that, Colorado-based Endolith is turning to microbes.

Today, most copper is mined using hydrometallurgy, which typically involves pouring acid on piles of rock, which removes some of the copper. Endolith supplements that by adding what are essentially domesticated microbes that can increase the amount of copper leaching from the pile.

“Conservatively, we think we can get 10% more copper,” Liz Dennett, founder and CEO of Endolith, told TechCrunch. The company is among the startups participating in the Startup Battlefield 200 at TechCrunch Disrupt 2024.

The industry will likely welcome anything that increases recovery rates. Mining for metals is like looking for a needle in a haystack. Prospectors spend hours searching for potentially profitable deposits. Then miners spend years digging them up and dousing them with chemicals to extract a small amount of the metal. In the case of copper, the rocks in a mine contain about 1% copper; only about half of that is typically mined, Dennett said.

To get 10 percent or more extra, Endolith starts by studying the conditions in a particular mine’s heap leach, as the stack is called. After taking samples from different parts of the stack, the startup inoculates the samples with microbes it thinks might be suitable. It then takes the most promising candidates and accelerates their evolution in the lab by exposing them to increasingly stressful conditions, such as high arsenic or saltwater, depending on the stack’s conditions. The result is a community of microbes that can release more copper from the rock.

“We’re turning normal microbes into Olympic-caliber athletes,” Dennett said.

Dennett, who has a PhD in geomicrobiology, previously served as CTO of Cemvita, a company that uses microbes to convert waste into more valuable materials. “The group I naturally gravitated toward was the biomining group,” she said. “The board asked me to come in and see if there was one. What do we do with it? Do we sell it? Do we spin it? What would it take to ultimately make this super successful?”

Last year, the company spun off Endolith as an independent entity, and Dennett began fundraising. Now, the startup has raised an oversubscribed $5.13 million seed round led by Collaborative Fund and Overture, with participation from Grok Ventures, Nomadic Venture Partners and Nucleus Capital, the company told TechCrunch exclusively.

“We got a term sheet within six weeks,” she said, adding that the round closed in about three months. Cemvita remains “a very small stakeholder,” Dennett added. “They have very little to do with our day-to-day operations.”

A big change for Cemtiva is reducing its product lines from five to two: copper and lithium. “We’ve been laser-focused,” she said. “Everyone loves the platform business until it’s time to commercialize it.