US-based NANO Nuclear Energy has announced development of a second proprietary advanced micro nuclear reactor design. ODIN is a low-pressure coolant reactor that “aims to diversify its technology portfolio, as the design requirements can be met through different technological solutions”.

This follows earlier announcements about its ZEUS advanced nuclear micro reactor designed to be modular and to connect with local power grids or power systems, “revolutionising recovery from natural disasters and how remote communities, mining project, and military bases, among others, obtain consistent electricity”. The company said it is “committed to building smaller, cheaper, and safer nuclear energy for the future by incorporating the latest technology into its own proprietary novel reactor designs, intellectual properties, and research methods”.

The ODIN design will utilise conventional sintered pellet uranium dioxide (UO2) fuel with up to 20% enrichment, “helping to minimise the required development and testing programme schedule and costs”. The low pressure coolant will “minimise the stress on structural components, improve their reliability and service life”. It will also “use a unique reactivity control system design, aiming to have high reliability and robustness through minimizing the number of moving parts”.

The reactor will operate at higher than conventional water-cooled reactor temperatures, which will allow resilient operation and high-power conversion efficiency in generating electricity. The “ODIN” design will aim to take maximum advantage of natural convection of coolant for heat transfer to the power conversion cycle at full power and for decay heat removal during reactor shutdown, operational transients, and off-normal conditions.

“Our second proprietary Advanced Nuclear Reactor design, ODIN adds another disruptive technology that we are confident will add enormous value to our company, said James Walker, NANO Nuclear Energy’s CEO & Head of Reactor Development. “We now have a portfolio of advanced, commercially driven, reactors being developed by world class technical teams, diversifying the products that NANO Nuclear will have available, while simultaneously opening further routes to success.”

The company website has extensive information on the global potential for nuclear in general and small reactors in particular. However, it has no information on the technology or reactor-type planned for either ZEUS or ODIN. It notes: “A handful of microreactor designs are under development and they could be ready to roll out within the next decade. These compact reactors will be small enough to transport by truck and could help solve energy challenges in a number of areas.”

Earlier in February, NANO Nuclear also established a subsidiary, HALEU Energy Fuel. The purpose of the new company is “to develop, improve, and accelerate the domestic production of High-Assay Low Enriched Uranium (HALEU) to meet the growing demand for the fuel required to power advanced nuclear reactors. HALEU fuel, enriched to between 5% and 20% with uranium-235, is needed for many advanced nuclear reactors under development. The industry anticipates it may need nearly 600 tonnes of HALEU by 2030.

Russia is currently the only commercial source of HALEU and accounted for nearly 40% of global uranium conversion services in 2020. The US Department of Energy (DOE) is now looking to develop its own HALEU production facilities in face of concerns about energy independence. It set up the HALEU Consortium in 2022 to support the availability of HALEU for civilian domestic research, development, demonstration, and commercial use. Following the formation of HALEU Energy Fuel, NANO Nuclear Energy was selected as a founding member of the Consortium.