Next-Gen Nuclear Funding Looks Livelier Than Ever Following Inertia’s $450M Raise

As global energy demand continues to

surge

, driven by both rising household consumption and fast-expanding AI infrastructure, startup investors are increasingly turning to nuclear fusion and fission startups to supply our power-hungry era.

They’re not afraid to write big checks either. The latest evidence of this was a $450 million Series A that Livermore, California-based fusion power startup

Inertia Enterprises

announced

Wednesday.

Bessemer Venture Partners

led the round for the 2-year-old company, joined by

Google Ventures

Threshold

and other backers. Inertia plans to use the funds toward a fusion pilot at

Lawrence Livermore National Laboratory

, which will involve building the world’s most powerful laser and a production line to mass manufacture

fuel targets

The financing is the latest in a string of recent, very large deals around both fusion and nuclear fission. Per Crunchbase data, both funding and deal volume for the space hit a high last year, and 2026 is off to a promising start as well.

Headline deals, leading fundraisers

It’s mostly funding announcements, but not exclusively. On the fusion front, the highest profile recently proposed deal was

Trump Media & Technology Group

’s

surprising announcement

in December that it plans to combine with fusion company

TAE Technologies

in what TMTG called a stock transaction valued at more than $6 billion.

The deal is a long time coming for TAE, which was founded in 1998 and is the oldest operating venture-backed fusion energy company in the Crunchbase dataset. The company has seen at least $1.5 billion in prior known funding to date.

Other fusion companies have also been prodigious fundraisers. The leader is

Commonwealth Fusion Systems

, with $2.86 billion in equity funding, while other standouts include

Helion Energy

($1 billion),

Pacific Fusion

($900 million) and

General Fusion

($357 million).

Nuclear fission is another

hot area for investment

, with over $2.5 billion in funding last year, per Crunchbase. The largest deal was a $700 million Series D in late November for

X-energy

, a developer of advanced nuclear reactor and fuel technology.

Activity looks to be accelerating further this year, with more than $270 million in funding, including a $140 million round two weeks ago for Tennessee-based

Standard Nuclear

, which manufactures advanced nuclear fuel for new reactors.

Public markets too

Public investors also appear receptive.

Oklo

, which develops nuclear reactors, went public in 2024 through a merger with a SPAC launched by

Sam Altman

. It’s down quite a bit from the height scaled late last year, but still had a recent market cap around $10 billion.

Other SPAC deals have also popped up, including

One Nuclear Energy

, which wants to develop energy parks with small modular reactors to meet data center demand, and

Hadron Energy

, a developer of light-water micro-modular reactors. Meanwhile

Terrestrial Energy

, a developer of small modular nuclear plants, completed a SPAC merger in October.

Related Crunchbase query:

Nuclear Energy-Related Startup Funding, 2025