Private Markets / Energy & Climate

Top Private Energy & Climate Companies by Valuation

Generation, storage, grid, and climate technology — the private energy transition ranked by valuation.

105tracked companies
$190Bcombined valuation
32daily secondary marks
-18.8%median vs last round
#CompanyValuationSecondary $/shvs Last RoundLast RoundIPO Status
1 Crusoe Energy Systems
Denver, Colorado
$30Bmark 2026-03 $169.56as of 2026-06-27 +101.8% Series E · 2025-10-23 · $1.4B Private
2 Helion Energy
Everett, WA
$16Bmark 2026-06 $65.00as of 2026-06-27 +55.5% Series G · 2026-06-01 · $425M no imminent plans
3 Base Power
Austin, TX
$13Bmark 2026-Q3 $100.16as of 2026-06-27 -14.9% Series D · 2026-08-03 · $1.0B private
4 Switch
Las Vegas, NV
$11Bmark 2022-Q4 no secondary mark Buyout/LBO · 2022-12-06 · $11B filed confidentially
5 Fervo Energy
Houston, TX
$10Bmark 2026-05 $12.32as of 2026-06-27 +50.8% Series D · 2024-09-01 · $244M no imminent plans
6 Octopus Energy
London, United Kingdom
$9.0Bmark 2024-12 no secondary mark PE Growth/Expansion · 2024-05-07 · $803M private
7 Valar Atomics
Hawthorne, CA
$6.0Bmark 2026-Q3 $61.53as of 2026-06-27 no round comparison Series B · 2026-08-01 · $1.0B private
8 Commonwealth Fusion Systems
Devens, MA
$5.0Bmark 2025-Q4 $196.22as of 2026-06-27 no round comparison Series B2 · 2025-08-01 · $863M no imminent plans
9 Joulent
Houston, TX
$5.0Bmark 2026-Q3 no secondary mark Strategic minority investment · 2026-07-01 · $1.8B private
10 Redwood Materials
Carson City, Nevada
$4.5Bmark 2025-Q4 $35.71as of 2026-06-27 -25.2% Series E · 2025-10-22 · $350M Private
11 HiTHIUM
Xiamen, China
$4.2Bmark 2023-Q2 no secondary mark Series C · 2023-06-30 · $629M private
12 Aurora Solar
San Francisco, CA
$4.0Bmark 2026-01 $15.05as of 2026-06-27 no round comparison Series D · 2022-02-14 · $200M private
13 Group14 Technologies
Woodinville, Washington
$3.0Bmark 2025-Q3 $11.12as of 2026-06-27 -56.4% Series D · 2025-08-20 · $463M Private
14 Workrise
Austin, TX
$2.9Bmark 2022-Q1 $74.16as of 2026-06-27 -82.3% Series E · 2021-04-01 · $300M private
15 TerraPower
Bellevue, WA
$2.5Bmark 2022-Q3 $55.37as of 2026-06-27 no round comparison Series E · 2022-08-01 · $830M no imminent plans
16 ProLogium
Taoyuan, Taiwan
$2.5Bmark 2021-Q3 $10.00as of 2026-06-27 no round comparison Series E · 2021-08-19 · $150M private
17 TAE Technologies
Foothill Ranch, California
$2.5Bmark 2025-Q2 $99.59as of 2026-06-27 no round comparison Series 12 · 2025-06-01 · $150M Merger pending with Trump Media & Technology Group
18 Enovate Motors
Shaoxing, China
$2.1Bmark 2026-08 no secondary mark Series B · 2020-10-13 · $736M private
19 Gradiant
Woburn, MA
$2.1Bmark 2026-Q2 $31.31as of 2026-06-27 +5.6% Series E · 2026-05-17 · $400M private
20 Panthalassa $2.0Bmark 2026-08 no secondary mark undisclosed Private
21 Aulton
Shanghai, China
$2.0Bmark 2021-Q3 no secondary mark Series B · 2021-09-29 · $232M private
22 SPIC Hydrogen Energy
Beijing, China
$1.8Bmark 2022-Q4 $0.66as of 2026-06-27 no round comparison 2022-12-07 · $631M private
23 Radiant
El Segundo, CA
$1.8Bmark 2025-Q4 $47.28as of 2026-06-27 +11.7% Series D · 2025-12-15 · $300M private
24 Watershed
San Francisco, CA
$1.8Bmark 2024-02-01 $7.55as of 2026-06-27 -22.6% undisclosed private
25 Form Energy
Somerville, MA
$1.8Bmark 2026-08 $16.76as of 2026-06-27 -30.7% Series F · 2024-10-01 · $405M no imminent plans
26 Sila Nanotechnologies
Alameda, California
$1.7Bmark 2026-Q2 no secondary mark Series G · 2026-04-07 · $475M none
27 KoBold Metals
Berkeley, CA
$1.7Bmark 2026-01 $86.78as of 2026-06-27 +2.2% Series C · 2025-01 · $537M private
28 Jinsheng New Energy
Zhaoqing, China
$1.7B no secondary mark Series C private
29 Nanotech Energy
Sunny Isles Beach, FL
$1.7Bmark 2021-Q3 no secondary mark Series E · 2021-09-02 · $158M private
30 Arcadia
Washington, DC
$1.5Bmark 2022-Q2 $10.72as of 2026-06-27 -43.4% Series E · 2022-05-10 · $200M private
31 Prometheus Fuels
Santa Cruz, CA
$1.5Bmark 2021-Q3 no secondary mark Series B · 2021-09-23 · $100M private
32 Helium Inc.
Calgary, Canada
$1.3Bmark 2022-Q1 $40.00as of 2026-06-27 -20.8% Series D · 2022-02-18 · $200M private
33 24M
Cambridge, MA
$1.3Bmark 2024-Q3 no secondary mark Series H · 2024-09-04 · $87M private
34 StoreDot
Herzliya, Israel
$1.3Bmark 2022-Q1 $7.02as of 2026-06-27 -61.0% Series D · 2022-03-21 · $70M private
35 Gecko Robotics
Pittsburgh, PA
$1.3Bmark 2026-01 $45.22as of 2026-06-27 -8.2% Series D · 2026-01-01 · $122M Private
36 ONE (Our Next Energy)
Novi, MI
$1.2Bmark 2024-Q1 $6.00as of 2026-06-27 -56.3% Early Stage VC · 2024-02-01 · $39M private
37 Avaada
New Delhi, India
$1.1Bmark 2021-Q3 no secondary mark Corporate · 2021-07-13 · $464M private
38 Zap Energy
Everett, WA
$1.1Bmark 2024-Q3 $25.00as of 2026-06-27 -77.7% Series D · 2024-07-30 · $130M private
39 Redaptive
Denver, CO
$1.1Bmark 2024-Q4 $8.92as of 2026-06-27 -16.9% PE Growth/Expansion · 2024-10-22 · $100M private
40 SOURCE
Norwood, MA
$1.1Bmark 2022-Q2 no secondary mark Series D · 2026-08-08 · $400M private
41 Emerald AI
Washington, D.C., USA
$1.1Bmark 2026-08 no secondary mark Strategic · 2026-03 · $25M private
42 Astronergy
Haining, China
$1.0Bmark 2023-Q1 no secondary mark Series B · 2023-01-06 · $216M private
43 Epirus
Torrance, California
$1.0Bmark 2025-Q1 $5.11as of 2026-06-27 -8.4% Series D · 2025-03-03 · $250M Private
44 Heron Power
Scotts Valley, California, USA
$1.0Bmark 2026-04 no secondary mark Series B · 2026-02-18 · $140M private
45 Span
San Francisco, CA
$1.0Bmark 2026-Q1 $15.78as of 2026-06-27 +34.1% Series C · 2026-01-27 · $163M private
46 Palmetto
Charlotte, NC
$1.0Bmark 2022-Q1 $4.28as of 2026-06-27 -41.6% Series C · 2022-02-23 · $375M private
47 Electric Hydrogen
Devens, MA
$1.0Bmark 2023-Q3 $2.16as of 2026-06-27 no round comparison Series C · 2023-07-25 · $380M private
48 EcoFlow
Shenzhen, China
$1.0Bmark 2021-Q2 $7.07as of 2026-06-27 no round comparison Series B · 2021-06-10 · $100M private
49 Lunar Energy
Mountain View, CA
$1.0Bmark 2026-Q1 $3.32as of 2026-06-27 no round comparison Series D · 2026-02-04 · $102M private
50 Radia
Boulder, CO
$1.0Bmark 2022-Q2 no secondary mark Series B2 · 2022-05-13 · $51M private

Most Active Investors in Energy & Climate

Ranked by tracked Energy & Climate portfolio companies — counted from disclosed round participation and each firm's notable holdings, so a firm only appears here if it actually holds companies in this ranking. Full capital-side ranking: Top Private Market Investors by AUM.

Frequently Asked Questions

What are the largest private Energy & Climate companies in 2026?

By latest disclosed valuation, the largest tracked private Energy & Climate companies are Crusoe Energy Systems ($30B), Helion Energy ($16B), Base Power ($13B), Switch ($11B), Fervo Energy ($10B). The full ranking of 105 companies refreshes daily at quantlogix.ai/private/energy.

Who are the most active investors in private Energy & Climate companies?

Ranked by tracked Energy & Climate portfolio companies, the most active investors are Energy Impact Partners (8 tracked), Breakthrough Energy Ventures (7 tracked), Founders Fund (6 tracked), Andreessen Horowitz (4 tracked), Valor Equity Partners (3 tracked). Full ranking: Top Private Market Investors by AUM.

How fresh are these Energy & Climate valuations and secondary marks?

Valuations are each company's latest disclosed mark, dated per row; secondary share prices refresh daily (32 of 105 tracked companies currently carry one). Rows without a usable number say so rather than showing zero.

Methodology. Rankings are by each company's latest disclosed valuation (roster + weekly enrichment); the "mark" chip shows when that valuation was set. Secondary share prices are point estimates from secondary-market activity — one implied price per name, no bid/ask — refreshed daily (marks overlay as of 2026-09-05), each carrying its own date. "vs Last Round" compares the secondary price to the company's own last primary round per-share price; rows without a usable comparison say so rather than showing zero. Companies marked acquired, defunct, or public are excluded. Educational data, not investment advice.