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Startup · United States

Mainspring Energy

HQ Menlo Park, CAFounded 2010201-500 employees

Mainspring Energy is a Menlo Park company that designs and manufactures linear generators, fuel-flexible onsite power units that convert natural gas, biogas, propane or hydrogen into electricity without combustion. It sells to utilities, data centers, commercial and industrial users, and is piloting the generator for the U.S. Air Force at Travis Air Force Base.

StartupFielded
Website
Total raised
$258M
1 round
Last round
$258M
Series E+ · Apr 14, 2025
Systems
1
Most mature: fielded
Mentions
4
Latest Oct 13, 2026

News4

Open in the news feed →

Funding1 round · $258M

Equity raised
$258M
Latest
$258MSeries E+ · Apr 14, 2025

Raised counts equity rounds; debt, secondary sales and grants are totaled separately. Amounts in other currencies are converted at the announcement month's average rate. A ~ marks an estimated or converted amount.

Systems1

Newest unveiled first. Open a system for its milestone timeline, components and sources.

Supply Chain1 facility

Facilities1

  • Mainspring Energy headquarters
    Headquarters · Menlo Park, CA, United States
    Operating
    Confirmed

People6

All 6 people →
  • Adam Simpson

    Chief Commercial Officer & Founder

  • Matt Svrcek

    Co-founder

  • Shannon Miller

    President & Founder

  • Haben Goitom

    General Counsel

  • Ryan Fletcher

    Chief Financial Officer

  • Tom Linebarger

    Chairman & Chief Executive Officer

Hiring Observations10 observed listings

View all 90 listings →

A sample of observed listings, not a total vacancy count. Availability may have changed since collection. Categories are inferred from job titles.

Company Metrics

LinkedIn employee profiles
539
Observed Oct 13, 2026
Bright Data / LinkedIn · Source ↗
LinkedIn followers
89,171
Observed Oct 13, 2026
Bright Data / LinkedIn · Source ↗

Employee-profile counts reflect LinkedIn profiles associated with the company, not verified headcount. One observation establishes a baseline; it does not establish growth.

Sources15

Show all 15 sources and supporting evidence

Profile2

  1. 1
    CompanyMainspring Energy Awarded U.S. Air Force Pilot Project for Multi-Fuel, Resilient Power Generation at Travis Air Force Base

    Mainspring Energy · Mar 4, 2026 · Supports Organization

    “awarded a contract by the United States Department of the Air Force (DAF) for a pilot program to test a Mainspring Linear Generator”
  2. 2
    DatabaseMainspring Energy - Crunchbase company profile

    Crunchbase · Supports Organization · x url

    “social_media_links: ["https://www.linkedin.com/company/mainspringenergy", "https://x.com/mainspringenrgy"]”

Systems2

  1. 3
    CompanyMainspring Energy Signs Landmark 1.6 GW Agreement with AEP for Reliable, Affordable Power Capacity

    Mainspring Energy · Oct 13, 2026 · Supports Organization · legal name, System

    “Mainspring Energy, Inc. has signed a landmark sales agreement with American Electric Power (AEP)”
  2. 4
    CompanyLinear Generator (LGen) Technology

    Mainspring Energy · Supports Organization, System

    “A Mainspring Linear Generator directly converts motion into electricity.”

Funding1

  1. 5
    CompanyMainspring Secures $258 Million in Financing to Scale Linear Generator Business; Adds Energy and Tech Leaders to Board

    Mainspring Energy · Apr 14, 2025 · Supports Funding round · amount, Funding round · investors

    “it has secured $258 Million in a Series F financing round”

Supply chain2

  1. 6
    DatabaseMainspring Energy - LinkedIn company profile

    LinkedIn · Supports Facility, Organization · employee range, Organization · linkedin url, Organization · website, Organization metric · employees in linkedin, Organization metric · followers

    “headquarters: Menlo Park, CA”
  2. 7
    CompanyJoin the Team | Careers at Mainspring Energy

    Mainspring Energy · Supports Facility

    “Explore roles in our Menlo Park HQ, manufacturing facilities, or remote field operations.”

People7

  1. 8
    CompanyMainspring Appoints Former Cummins Chair & CEO Tom Linebarger as CEO & Founder Shannon Miller as President to Power Next Wave of Growth

    Mainspring Energy · Jun 10, 2026 · Supports Organization · founded year, Organization · hq city, Role

    “since co-founding the company in 2010”
  2. 9
    CompanyHaben Goitom

    Mainspring Energy · Supports Role

    “Haben Goitom, General Counsel”
  3. 10
    CompanyRyan Fletcher

    Mainspring Energy · Supports Role

    “Ryan Fletcher, CFO, joined Mainspring in 2019”
  4. 11
    DatabaseMatt Svrcek - Executive Bio - Equilar ExecAtlas

    Equilar · Supports Role

    “Matt Svrcek co-founded Mainspring”
  5. 12
    CompanyAdam Simpson

    Mainspring Energy · Supports Role

    “Chief Commercial Officer & Founder”
  6. 13
    CompanyShannon Miller

    Mainspring Energy · Supports Role

    “President & Founder”
  7. 14
    CompanyTom Linebarger

    Mainspring Energy · Supports Role

    “Chairman & Chief Executive Officer”

Other1

  1. 15
    CompanyMainspring Energy public job board

    Supports Job posting

    “Senior Field Service Technician (Long Island, NY)”

Each fact on this page is attached to the sources that support it. Archived copies are linked when we keep one.