Terrestrial Energy and ANSTO Sign Agreement for Used IMSR Fuel Management

Sydney, Australia and Oakville, Ontario, Canada, February 2, 2022 – ANSTO, Australia’s knowledge centre for nuclear science and technology, and Terrestrial Energy have agreed to explore ANSTO Synroc® (synthetic rock) proprietary waste treatment technology for used fuel management.

Under the agreement, ANSTO will provide technical consulting services to Terrestrial Energy for the conditioning of used reactor fuel from the operation of Integral Molten Salt Reactor (IMSR®) heat and power plants in Canada, United Kingdom, United States, and other global markets. Terrestrial Energy’s IMSR® uses molten salt reactor technology, a Generation IV nuclear technology, to produce cost-competitive carbon-free heat for industrial applications and generating electricity.

ANSTO Synroc is an Australian innovation offering a safe, cost-effective solution for the final disposal of complex intermediate and high-level radioactive waste. ANSTO Synroc is based on crystalline or mineral phases that have survived in natural geological environments at elevated temperatures in the presence of water for hundreds of millions of years.

ANSTO Synroc waste treatment technology delivers a tailored wasteform chemistry with associated process technology. These safely and securely accommodate a broad range of wasteforms that meet international requirements for long-term disposal of used reactor fuel. The Synroc innovative nuclear waste treatment technology also significantly reduces the volume of waste for disposal, lowering long-term lifecycle costs.

“ANSTO Synroc’s team has substantial experience in developing and progressing solutions for used fuel streams, and we are excited to share the benefits of this new Synroc innovation with Terrestrial Energy,” said Gerry Triani, Synroc Technical Director at ANSTO. “Terrestrial Energy’s used fuel management program has similarities to the ANSTO Synroc Radioactive Waste Treatment Facility, which will treat the liquid waste from radiopharmaceutical production.”

“Synroc waste treatment technology delivers the standards of safety and security of IMSR® used reactor fuel that society expects and regulators demand. These standards are essential for the expansion of nuclear energy generation to meet the challenges of our clean energy transition,” Simon Irish, Chief Executive Officer of Terrestrial Energy said of the partnership. “In many ways, this technology completes the IMSR®’s fuel cycle, from rock to clean energy production, and back to rock again, and from where we drew inspiration when naming the company, Terrestrial Energy.”

The development of the ANSTO Synroc Facility in Sydney is funded by the Australian Government as part of the ANSTO Nuclear Medicine project. It is intended to lock-up the radioactive byproducts from the production of life-saving radioactive isotopes, used widely in medical imaging for the diagnosis of many diseases.

About Terrestrial Energy

Terrestrial Energy is a developer of small and modular nuclear power plants that use its proprietary Integral Molten Salt Reactor (IMSR®) technology. The IMSR® is a non-Light Water Reactor that uses Generation IV technology to generate electricity 50 percent more efficiently than conventional nuclear reactor technology. The IMSR® represents a step-change improvement in economics, versatility and functionality of nuclear power plants that is possible only through Generation IV technology. IMSR® power plants will provide resilient, reliable, dispatchable, zero-carbon and cost-competitive electric power, as well as high-grade industrial heat for use in many industrial applications, such as chemical synthesis, hydrogen production and desalination, and in so doing extend the application of nuclear energy far beyond electric power markets. IMSR® power plants have the potential to make important contributions to industrial competitiveness, energy security, and economic growth. Their deployment will support rapid global decarbonization of the primary energy system by displacing fossil fuel combustion across a broad spectrum and can scale to meet net-zero policy goals of major industrial economies. Using an innovative design, and proven and demonstrated molten salt reactor technology, Terrestrial Energy is engaged with regulators and industrial partners to complete IMSR® engineering and to commission the first IMSR® power plants within a decade.


ANSTO is one of Australia’s largest public research organisations and is widely recognised as an international player in the field of nuclear science and technology. Its vision is to be a global nuclear science, research, and engineering partner, with a reputation for tackling complex problems and delivering outcomes to create a more sustainable world. ANSTO works across areas such as health, the environment, and the nuclear fuel cycle to find solutions to some of the biggest questions in science for the benefit of all Australians. ANSTO also provides the Australian and international community with products and services to improve human health, support industry, and protect the environment.

Learn More About Terrestrial Energy

Terrestrial Energy is an industry-leading technology company committed to delivering reliable, emission-free, and cost-competitive nuclear energy with a truly innovative advanced reactor design, the Integral Molten Salt Reactor (IMSR®).