Aramco backs 1,742°F reactor running 1,100°F hotter than standard nuclear

ZettaJoule, a Texas-based company, has secured formal backing from Aramco Services Company for its advanced high-temperature gas-cooled reactor (HTGR), designed to produce process heat at 950°C (1,742°F)—about 600°C hotter than conventional water-cooled nuclear reactors. This small modular reactor (SMR) builds on proven technology originally developed by Japan Atomic Energy Agency’s High-Temperature Engineering Test Reactor (HTTR), which began operation in 1998. Aramco’s support, expressed in a letter to the US Departments of Energy and Commerce, aims to accelerate development and signal the technology’s commercial viability to global investors. The partnership reflects growing industry interest in nuclear thermal energy as a means to decarbonize heavy industrial processes requiring extreme heat. The ZJ reactor leverages established, safety-tested engineering rather than experimental designs, positioning it as a reliable reference model for future commercial industrial applications. ZettaJoule’s leadership expressed strong confidence in the project’s