Mainspring

Private

Menlo Park, CaliforniaEnergy & Sustainabilityhttps://www.mainspringenergy.com/

Last Round

Series F

Apr 14, 2025

Total Funding Raised

$773M

Company Overview

Mainspring Energy is a cleantech company that manufactures and delivers an innovative, fuel-flexible on-site power generator designed to accelerate the transition to a zero-carbon electric grid.

Sector

Energy & Sustainability

Verticals

Renewable Energy, Energy Management, Alternative Fuels, Smart Grid

Business Model

B2B

Customer Profile

Hardware Sales, Hardware + Subscription, Government Contracts, Services & Consulting

AI Layer

Application

Keywords

linear generatoron-site power generationfuel-flexible generatorenergy-as-a-serviceEaaSdispatchable powermicrogriddata center powerdistributed energy resourcesDERsbehind-the-meter generationpower purchase agreementPPAhydrogen power generationprime powernon-combustion reactioncommercial and industrial powerammonia power generation

Historical Pricing

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Mainspring Comps

Public and private peers based on sector, stage, and business model.

Mainspring comps — public and private peers by sector, stage, and business model
Company	Status	Est. Valuation	Rev Multiple
OpenAI	Private	$86.0B	~40x
Cohere	Private	$5.0B	--
Competitor 1	Public	$XX.XB	XXx
Competitor 2	Public	$XX.XB	XXx

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Mainspring Funding Rounds

Historical fundraising activity

Data table
Round	Date	Amount Raised	Valuation	Investors	Sources
Series F	Apr 14, 2025
Series E	Sep 21, 2022
Series D	May 4, 2021
Series C	Jan 24, 2018
Series B	Aug 17, 2012

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Mainspring Investors

Notable investors and investment history

Mainspring investors
Investor	Rounds
CPP Investments	Series E
Pictet Group	Series F
40 North Ventures	Series D
Fine Structure Ventures	Series E
Temasek	Series F
Khosla Ventures	Series F, Series C, Series E, Series D, Series A, Series B
Princeville Capital	Series E, Series D

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Mainspring Filings

SEC and related filings with document metadata.

Data table
Typed	Date	Amount Offered	Amount Sold	Filling	Pages	Download
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Mainspring Filings

SEC and related filings with document metadata.

Frequently Asked Questions

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Firmographic Details

HeadquartersMenlo Park, California

Year Founded2010

Last FundingApr 14, 2025

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