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Mainspring raises $150M for linear generators

Illustration of power switches turned "on" surrounded by abstract shapes and dollar elements.

Illustration: Gabriella Turrisi/Axios

The onsite-power startup Mainspring Energy has raised more than $150 million in the first close of its Series E, and will be deploying up to 150 of its linear generators in the next two years.

Why it matters: The double-barreled announcement reflects significant buy-in from major players — Khosla Ventures and Bill Gates, and industrial customer Lineage Logistics.

What's happening: Other investors include Lightrock, a growth equity investor that led the series E, and existing investors Fine Structure Ventures and Princeville Capital.

  • Mainspring did not disclose the total it intends to raise in the round, but says it will use the funds to develop new generator models and accelerate deployment.

Meanwhile: Lineage Logistics, a warehousing and logistics management company that bought two Mainspring generators in November, has agreed to purchase as many as 150 of the generators through the next two years — a deal representing "more than $100 million," Mainspring founder and CEO Shannon Miller tells Axios.

The bottom line: "The market is definitely on a roller-coaster ride," Miller says.

  • "We’ve seen fluctuations in the public companies, so I’m not sure if stage had a lot to do with it or not. A lot of the trouble is coming from the SPAC market having a lot of companies going out with high valuations and then having this market correction now coming in. We’ve avoided that kind of cycle."

Editor's note: This article has been updated to reflect that Mainspring raised more than $150 million in its Series E, rather than $100 million which was the total in a draft of the press release provided to the reporter.

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