Mainspring Raises $95 Million in Series D Financing for New Linear Generation Technology

May 7, 2021
Mainspring Energy plans to use the funding to accelerate the delivery of its linear generators for commercial, industrial, microgrid and utility customers.

California-based cleantech startup Mainspring Energy has raised $95 million in a Series D financing round led by the private equity firm Devonshire Investors. Mainspring Energy plans to use the funding to accelerate the delivery of linear generators that it uses in microgrids and commercial, industrial and utility applications.

The company plans to scale deployments with a 50% increase in staff as well as expanded manufacturing operations. 

With the latest $95 million raised from investors such as 40 North Ventures, Chevron Technology Ventures and Princeville Capital, Mainspring has now reached a total working capital of $228 million to help achieve its vision of a more affordable and reliable net-zero carbon grid.

Prior to the Series D round, Mainspring entered into a $150 million unit purchase, project financing agreement and distribution partnership with Nextera Energy Resources. 

To date, Mainspring’s portfolio of high-profile investors also includes Bill Gates, AEP, ClearSky, KCK and Khosla Ventures.

Mainspring’s linear generators are positioned to help increase localized energy reliability with detachable, fuel-flexible power solutions. Mainspring CEO Shannon Miller cited “increasing incidence of extreme weather events and related power outages” driving demand for its product. 

Currently, the linear generators are designed to allow energy users to seamlessly toggle between 100% renewable fuels such as wind and solar. Advancements are also being made to incorporate biogas and hydrogen. 

Besides its commercial and utility customers, Mainspring is targeting a wide range of microgrid customers for its linear generator technology. The company recognizes opportunities for increased energy resilience in such settings as college campuses, data centers, medical facilities and residential communities.

With accelerated production and delivery of products, Mainspring hopes to increase its share in the distributed energy industry, which market research company Guidehouse Insights has estimated to reach $212 billion by 2030. 

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About the Author

Brian Church

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