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Mainspring's linear generator. Photo courtesy of Mainspring.

The distributed generation company Mainspring Energy has raised $95 million in new funding led by Fidelity Investment's private equity arm, alongside other new and existing backers like Chevron, Princeville Capital and Bill Gates.

Why it matters: There's growing interest in low-carbon onsite power sources as a way to fight climate change and to create more flexibility and resilience as grids are increasingly stressed by extreme weather.

How it works: The Bay Area firm's technology, called a "linear generator," is designed to run on multiple fuels.

  • It uses a "low-temperature reaction of air and fuel to drive magnets through copper coils to efficiently produce electricity."
  • CEO Shannon Miller has likened it to "an air hockey table that you’ve wrapped around into a tube."

Where it stands: Mainspring — founded by Stanford engineers in 2010 and formerly called EtaGen — said the new money brings its total capital raised to $228 million.

  • The Series D financing will enable Mainspring to add customer deployments, expand manufacturing and add staff, the company said.
  • It comes about two months after Mainspring announced a $150 million deal with power heavyweight NextEra Energy Resources to buy Mainspring units and finance customer projects.

Go deeper: Clean energy patenting is outpacing fossil fuels, but experts warn it's not enough

Go deeper

Biden administration approves massive solar energy project in California

A solar farm in California. Photo: Sam Lafoca/Construction Photography/Avalon/Getty Images

The Interior Department announced Monday that it has approved a massive solar energy project on California's public lands.

Why it matters: The $550 million project will produce enough energy to power nearly 90,000 homes.

GOP Rep. Clay Higgins says he has COVID for second time

Rep. Clay Higgins during a 2019 House Oversight and Reform Committee hearing on Capitol Hill. Photo: Tom Williams/CQ Roll Call

Rep. Clay Higgins (R-La.) Sunday evening that he and his wife have contracted COVID-19 for a second time and "this episode is far more challenging."

Driving the news: "Becca and I had COVID before, early on, in January 2020, before the world really knew what it was," he wrote in a Facebook post, confirming his son also has the coronavirus — which he described as a "biological attack weaponized virus."

Updated 1 hour ago - Sports

Olympics dashboard

📺: The Olympic events to watch today; Olympics opening ceremony ratings plunge

🏊: Athlete spotlight — Katie Ledecky adds to Games career medals haul; Caeleb Dressel leads Team USA to gold.

🏀: U.S. Men's basketball suffers first Olympic loss since 2004

🤖: The robot Olympics

🚨: Heat wave brings scorching temperatures to Tokyo Olympics

🎤: Meet the new faces of NBC's Olympics coverage

Go deeper: Full Axios coverage