A New Era of Nuclear
Join us in our mission to bring proven advanced nuclear technology to the world.
Former Mitsubishi Heavy Industries Executive Yasushi Fukuizumi Joins ZettaJoule, KK as Deputy CEO.
Our reactor design will include the ability to operate at temperatures up to 950 °C, which is approximately 600 °C higher than conventional water-cooled reactors. The first ZJ project will serve as a reference reactor for future commercial deployments.
What Sets Us Apart
The decades-long operating history of Japan’s HTTR, supported by extensive publicly available data, provides a strong foundation for ZettaJoule’s modernized technology. This enables a more predictable licensing and construction pathway compared to first-of-a-kind SMR concepts.
Proven Technology
We stand alone among Western advanced SMR companies in modernizing proven, publicly available high-temperature gas-cooled reactor (HTGR) technology based on an existing plant. Data from the Japan Atomic Energy Agency’s High Temperature Engineering Test Reactor (HTTR), in operation since 1998, provide the foundation for ZettaJoule’s advanced SMR technology.
Impact Across Industries
With the ability to generate unmatched heat up to 950 °C and provide reliable electricity, the ZettaJoule advanced SMR will unlock transformative energy solutions across sectors such as oil and gas, mining, chemical manufacturing, sustainable aviation fuel production, steelmaking, data centers, e-fuels, and utilities.
Built for Safety
ZettaJoule’s ZJ reactor will be graphite-moderated and helium-cooled to enhance operational safety while improving overall performance. It will use TRISO fuel consisting of uranium particles individually encapsulated in multiple protective layers of pyrocarbon and silicon carbide, which retain fission products even at temperatures as high as 1600 °C.
"This is an exciting time for our company, and we are fully prepared to move the ZJ reactor project forward with support from public and private partners."
Common Questions
We stand alone among Western advanced small modular reactor companies in our modernization of proven, publicly available High-Temperature Gas-Cooled (HTGR) technology based on an existing plant (the HTTR which has been in operation since 1998) - not just a concept.
With the ability to operate at 950 °C, our ZJ reactor will unlock transformative energy solutions across key industrial and commercial sectors – including oil and gas, chemical manufacturing, synfuels, mining, aviation, maritime, steelmaking, data centers, and utilities.
Our team is led by individuals who have directed multi-billion-dollar projects across the globe. Now united at ZettaJoule, these industry leaders are combining their extensive cross-disciplinary experience in nuclear engineering, advanced reactor design, artificial intelligence, fuel cycles, regulations and licensing, gas turbines, mining, and investment banking to develop innovative nuclear energy solutions for industrial, tech and commercial sectors – in a rapidly emerging multi-trillion-dollar global energy market.
Our initial advanced SMRs will deliver 30 MWth with future designs scaling to 600 MWth.
Our 30 MWth advanced SMR plants will be approximately 30 meters by 30 meters (~33 yards by 33 yards) – sufficiently compact for placement close to industrial or commercial operations and in remote locations.
Given its inherent safety, the Emergency Planning Zone (EPZ) could be contained entirely within the site’s security-fenced exclusion area, with a radius of approximately 250 meters (~273 yards).
Our reactors will be available as single or multiple modules, giving customers flexibility based on their energy needs without having to commit to a massive reactor facility. Customers will be able to purchase energy as off-takers.
We plan to deploy an advanced SMR research reactor initially, which can often be licensed on a shorter timeline than a commercial reactor while also providing operating data to help streamline licensing for subsequent commercial reactors.
ZettaJoule is backed by global venture capital investors.
