50 Best Energy Nuclear Startups in United States to Watch in 2025

The Definitive Seedtable Ranking of Energy Nuclear Startups in United States

We track 71,000+ companies and rank them dynamically using our Seedtable Score – a score that uses quantitative and qualitative data points to signal the momentum behind a company. We then monitor the list manually leveraging our expertise as founders and investors.

There are 50 start-ups with an aggregate funding of $11.5b. The average funding per company in this subset is $229.8m.

Last update to the database: Jun 10, 2025. See changelog.

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5

Funding Rounds

$2.1b

Money raised

Commonwealth Fusion Systems is a Cambridge, Massachusetts-based research and development company developing fusion power systems based on ARC tokamak reactors.

5

Funding Rounds

$18.4m

Money raised

WiBotic is a technology company specializing in wireless charging and power optimization solutions.

Key people:

8

Funding Rounds

$28.3m

Money raised

Verdigris is a California-based company developing smart grid and energy management technology aided by artificial intelligence. It was founded by Mark Chung, Thomas Chung, and Jonathan Chu.

5

Funding Rounds

$2.7b

Money raised

Nikola Motor Company is a Phoenix, Arizona-based automotive company founded in 2014 by Trevor Milton.

7

Funding Rounds

$695.0m

Money raised

Aurora Solar is a San Francisco-based developer of solar design, proposal, and sales software.

11

Funding Rounds

$528.2m

Money raised

Stem is a Millbrae, California-based developer of solutions for energy consumption through a combination of data, predictive analytics, and energy storage to reduce energy costs.

6

Funding Rounds

$225.0m

Money raised

FreeWire Technologies is a San Leandro, California-based provider of battery systems for electric vehicle charging and mobile distributed power.

4

Funding Rounds

$875.0m

Money raised

Sila Nanotechnologies is an Alameda, California-based company engineered materials company focused on improving energy storage.

5

Funding Rounds

$162.0m

Money raised

Sense is a Cambridge, Massachusetts-based developer and distributor of energy tracking and automation solutions. Sense specializes in tracking devices and home automation solutions for its customers.

6

Funding Rounds

$72.0m

Money raised

OhmConnect is a company founded in 2013 by Curtis Tongue, Matt Duesterberg and Cadir Lee.

Key people:

1

Funding Rounds

$2.6m

Money raised

R&D lab focused on energy, manufacturing, & innovation.

5

Funding Rounds

$23.8m

Money raised

A company developing technology to increase the energy density of lithium-ion batteries

Key people:

3

Funding Rounds

$85.0m

Money raised

GHGSat is a Montreal-based company developing sensors to monitor industrial emissions.

4

Funding Rounds

$537.4m

Money raised

Developer of software-defined high power microwave (HPM) technology designed to counter unmanned aircraft systems (UAS). The company's technology addresses threats such as drones and other asymmetric technologies, enabling defense organizations to stun drones with a hard reset or knock swarms out of the sky.

10

Funding Rounds

$21.3m

Money raised

Prieto Battery, Inc. is a company that focuses on commercializing patented Lithium-ion battery technology.

Key people:

8

Funding Rounds

$181.0m

Money raised

Fulcrum Bioenergy is a Pleasanton, California-based biofuel and clean technology company.

Key people:

4

Funding Rounds

$512.5m

Money raised

Crusoe Energy Systems is a company founded in 2018 by Chase Lochmiller.

3

Funding Rounds

$1.2m

Money raised

Dreamweaver International is a company that produces lithium-ion battery separators, founded by Brian Morin.

2

Funding Rounds

$35.0m

Money raised

Palmetto is a company founded in 2008.

1

Funding Rounds

$30.0m

Money raised

SunShare is a company founded in 2011.

Industries:

Location:

3

Funding Rounds

$104.8m

Money raised

EcoFlow is a mobile power company that is reinventing the way the world accesses energy.

1

Funding Rounds

$8.0k

Money raised

Volt Markets is a blockchain company founded in 2016 by Rob Hitchens, Dan Nossa and James Duchenne.

14

Funding Rounds

$82.5m

Money raised

ViZn Energy Systems is a company founded in 2009 by Craig Wilkins.

5

Funding Rounds

$261.9m

Money raised

6K is a North Andover, Massachusetts and New Cumberland, West Virginia-based custom fabrication and additive manufacturing company.

11

Funding Rounds

$82.6m

Money raised

Nanoramic Laboratories is a materials solutions innovator and energy storage technology company.

Location:

Key people:

8

Funding Rounds

$14.1m

Money raised

Graphenix Development Inc. is a developers of energy density electrodes founded in 2010 by Robert Anstey.

5

Funding Rounds

$792.0m

Money raised

Redwood Materials is a battery recycling company founded in 2017.

1

Funding Rounds

Fenix International is a company founded in 2009 by Mike Lin.

1

Funding Rounds

$3.0m

Money raised

Cybersaint provides cybersecurity management solutions for organizations, automating compliance and risk assessments.

1

Funding Rounds

$14.0m

Money raised

KeraCel develops multi-material 3D additive manufacturing methods for application in active electro-mechanical devices.

3

Funding Rounds

$360.0k

Money raised

TEQ Charging increases affordability and accessibility of electric vehicle charging.

Key people:

4

Funding Rounds

$550.0k

Money raised

Its mission is to offer the Solar Site Design information technology platform to solar professionals worldwide.

2

Funding Rounds

$7.0m

Money raised

Greenlots is a company founded in 2017 by Ron Mahabir.

2

Funding Rounds

$548.0m

Money raised

Onsite power generation for the zero carbon future

1

Funding Rounds

$500.0k

Money raised

American Aerospace Technologies, Inc. is a company founded in 2002 by David Yoel.

1

Funding Rounds

$65.0m

Money raised

Ionic Materials is a battery manufacturing company.

1

Funding Rounds

$50.0k

Money raised

SYNCFAB is a company founded in 2013 by Andy Tong.

3

Funding Rounds

$4.0m

Money raised

Natrion is a company founded in 2018 by Thomas Rouffiac.

2

Funding Rounds

$418.0m

Money raised

Group14 Technologies is a Woodinville, Washington-based battery manufacturing company.

1

Funding Rounds

$10.0m

Money raised

Ocean Renewable Power Company is a company founded in 2004.

1

Funding Rounds

$1.5m

Money raised

Lucid Energy is based in Portland, Oregon in the United States. They specialize in harvesting power from moving water in industrial, agricultural, and municipal settings. The key to the technology is that it generates electricity from sources that would otherwise be lost. In other words, it is an energy recycling system. The net result is installations reduce overall energy requirements.

6

Funding Rounds

$112.7m

Money raised

Vionx Energy is a company founded by Gary Colello.

1

Funding Rounds

SOLARCYCLE is a technology-driven platform designed to maximize solar sustainability by offering solar asset owners a process for recycling retiring solar panels and technologies and repurposing them for new uses.

3

Funding Rounds

$29.0m

Money raised

Firefly Energy is a company founded in 2003.

2

Funding Rounds

$36.0m

Money raised

Ioxus is a company founded in 2007.

1

Funding Rounds

$100.0k

Money raised

Dynamhex is a personalized, localized, and standardized climate action platform.

1

Funding Rounds

$150.0k

Money raised

Nanogrid is a company founded in 2017 by Patrick Sheehan.

1

Funding Rounds

$2.5m

Money raised

AI-powered all-in-one platform for rooftop solar installers.

Key people:

1

Funding Rounds

$4.1m

Money raised

Momentum Solar is a company founded in 2009.

1

Funding Rounds

$2.6m

Money raised

Groom Energy Solutions is a United States-based company in the energy industry.

Industries:

Location:

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