Kairos Power company profile: valuation, funding & revenue

This Kairos Power company profile covers the company's valuation, revenue, funding rounds, investors and history. Kairos Power works in energy, with a focus on advanced nuclear fission. It was founded in 2016 and is headquartered in Alameda, California, United States. Every figure links to a public source, and anything the company hasn't disclosed is marked as such.

Revenue

Funding history

Kairos Power timeline

Key dates from the sources on this page, oldest first. Metric snapshots are listed after the funding events.

• 2016 — Kairos Power is founded in Alameda by Mike Laufer (CEO) and Per Peterson.
• 2026 (reported) — Late-stage funding: US$643M (including DOE support, reported). Investors: Investors including GV and Samsung C&T; US Department of Energy.
• 2024 — Google agreement: Up to 500 MW of advanced nuclear capacity by 2035.
• 2024 — DOE support for Hermes: Up to US$303 million (Advanced Reactor Demonstration Program).
• 2026 — Reported funding: US$643 million, including about US$368 million from investors and US$275 million from the DOE (reported).

Investors

Kairos Power is a California company building a new kind of nuclear reactor, cooled by molten fluoride salt instead of water. It has a deal to supply Google with up to 500 megawatts of nuclear power by 2035, is building test reactors in Tennessee, and was reported in 2026 to have raised about US$643 million. It has never disclosed a valuation. This profile explains Kairos's technology, its funding, its Google partnership and the challenges ahead.

Funding and valuation

Unusually for a nuclear startup of its size, Kairos was funded for years mainly by its founders and private backers rather than headline venture rounds, alongside large government support. In 2026 Dealroom reported a raise of about US$643 million to build reactors for Google, and Energy Central described the total as about US$368 million from investors including GV and Samsung C&T plus about US$275 million from the US Department of Energy. The exact date of that announcement was not clear in the reporting.

Kairos has not disclosed an equity valuation, so we do not show one. Any figure quoted online is an estimate.

The technology

Kairos's design is a fluoride salt-cooled high-temperature reactor. It uses TRISO fuel, tiny particles of uranium coated in layers of carbon and ceramic that retain radioactive material at very high temperatures, packed into pebbles. The coolant is a molten fluoride salt called Flibe, which can carry heat at high temperatures and low pressure. Low-pressure operation removes some of the safety and cost burdens of conventional water-cooled reactors, which run at high pressure, and high temperatures make the plant more efficient and useful for industrial heat as well as electricity.

The company's approach is iterative: build a series of test units quickly, learn from each, and bring manufacturing in-house, much as aerospace companies build and test hardware repeatedly.

Hermes, Hermes 2 and the Google deal

Kairos is building its Hermes demonstration reactor at Oak Ridge, Tennessee, under a construction permit from the US Nuclear Regulatory Commission, and later received a permit for Hermes 2, a larger plant designed to produce electricity. The Department of Energy is supporting Hermes with up to US$303 million under its Advanced Reactor Demonstration Program, according to ExecutiveGov, and Kairos has a contract for high-assay low-enriched uranium (HALEU) fuel for the project, as reported by the American Nuclear Society.

In 2024 Google agreed to buy power from a fleet of Kairos reactors totalling up to 500 megawatts by 2035, one of the first corporate deals for small modular reactors. The first unit, Hermes 2, is expected to supply about 50 megawatts to the grid around 2030, through the Tennessee Valley Authority, according to Wikipedia. Kairos broke ground on the site in April 2026.

Founders

Mike Laufer, the chief executive, and Per Peterson, a nuclear engineering professor at the University of California, Berkeley, founded Kairos in 2016, building on years of university research into salt-cooled reactors. The company has grown to hundreds of employees across California, New Mexico and Tennessee.

Why AI companies want nuclear power

Data centres for AI need large amounts of electricity around the clock, and technology companies have committed to clean energy targets. Solar and wind are intermittent, and batteries cannot yet cover long gaps economically. Nuclear power offers carbon-free, always-on electricity, which is why Google, Amazon, Microsoft and Meta have all signed nuclear deals. See our guide to nuclear energy startups.

Competitive landscape

Kairos competes with other advanced reactor developers, including X-energy (which listed on Nasdaq in 2026), TerraPower, Valar Atomics, Radiant, Oklo and NuScale, and with fusion companies that promise power later. Each uses different fuel and cooling choices. Kairos's distinguishing features are its salt coolant, its iterative build approach and an anchor customer in Google.

How Kairos plans to sell power

Kairos does not intend to sell reactors as one-off projects. Its Google agreement is structured around power delivered to the grid through a utility, the Tennessee Valley Authority for the first unit, with Google paying for the clean electricity attributed to its operations. That model lets a technology company support new nuclear capacity without owning a reactor, and gives Kairos a creditworthy buyer for its first plants. If its designs work, Kairos aims to build reactors repeatedly in a standard form, which is where most of the hoped-for cost reductions in small reactors come from.

Risks

• First-of-a-kind cost and delay: new reactors almost always take longer and cost more than planned.
• Licensing: each step needs regulatory approval, though Kairos has already secured key permits.
• Fuel supply: HALEU and TRISO fuel are in short supply.
• Materials: molten salts are corrosive, and components must last for decades.
• Customer concentration: much of its near-term demand depends on one large buyer.

Questions to ask

• When will Hermes reach operation, and what will it prove?
• What will power from Hermes 2 cost per megawatt-hour?
• How secure is its fuel supply chain?
• How many reactors could it build per year once in production?

Timeline in brief

• 2016: founded by Mike Laufer and Per Peterson.
• 2023: NRC construction permit for Hermes in Oak Ridge.
• 2024: Hermes 2 permit; Google agreement for up to 500 MW.
• April 2026: breaks ground on the Hermes 2 site.
• 2026: reported raise of about US$643 million including DOE funds.
• Around 2030: first power to the grid targeted.

Kairos Power at a glance

Kairos Power is an Alameda, California nuclear company founded in 2016 by Mike Laufer and Per Peterson. It is developing fluoride salt-cooled high-temperature reactors using TRISO fuel, building the Hermes demonstration reactors in Oak Ridge, Tennessee, with up to US$303 million of DOE support. Google agreed to buy up to 500 MW from Kairos reactors by 2035. It was reported in 2026 to have raised about US$643 million, including DOE funding, and has not disclosed a valuation.

What to watch

Watch for Hermes operations, progress on Hermes 2, fuel deliveries, new customers beyond Google and any disclosed valuation. Our climate tech guide covers related companies.

Takeaways

Kairos is one of the most advanced private nuclear developers in the US, with permits, a government partner and a major technology customer. Its success depends on delivering working reactors on time and at a competitive cost, the challenge that has defeated many nuclear projects before it.

Sources

Every figure on this page comes from the public sources below. Where sources disagreed, we used the company's own announcement or a primary news report. Private-company data changes; check the date beside each figure.

1. Wikipedia
2. ExecutiveGov
3. Energy Central
4. Dealroom