Copenhagen Atomics

Copenhagen Atomics is a Danish molten salt technology company developing mass manufacturable molten-salt reactors. The company is pursuing small modular, molten fuel salt, thorium fuel cycle, thermal spectrum, breeder reactors using separated plutonium from spent nuclear fuel as the initial fissile load for the first generation of reactors.

Copenhagen Atomics' headquarters and production facility is located in Kastrup close to Copenhagen Airport.

History

Copenhagen Atomics was founded in 2014 by a group of scientists and engineers meeting at Technical University of Denmark and around the greater Copenhagen area to discuss thorium and molten salt reactors, which were later incorporated in 2015.

In 2016, Copenhagen Atomics was part of MIMOSA, a European nuclear molten salt research consortium.

In 2019, Copenhagen Atomics moved premises from a basement at the Technical University of Denmark to a location at the Alfa Laval company premises with production facilities. In 2023, Copenhagen Atomics closed an investment round of €25 million and moved to a larger headquarters and test facility at Kastrup, near Copenhagen Airport.

By the end of 2022, Copenhagen Atomics finished a full-size prototype reactor. The prototype is a full-scale test platform, that tests the system in its entirety, with water as its medium. In 2023 a full-scale prototype molten salt reactor was built to test the entire system with non-radioactive molten salts.

In May 2023, Copenhagen Atomics signed a memorandum of understanding with the Scandinavian companies Topsoe, Alfa Laval and Aalborg CSP, and Indonesian companies Pupuk Kalimantan Timur and Pertamina New and Renewable Energy, with the prospect of establishing a green ammonia plant in Bontang, Indonesia, powered by nuclear energy.

In July 2024, Copenhagen Atomics announced that their prototype reactors are ready to be tested in a real life scenario, in a critical experiment at the Paul Scherrer Institute in Switzerland. Originally planned to start tests in 2026-27, this would be the first time in European history that a critical experiment is carried out with a thorium molten salt reactor.

In 2025, Copenhagen Atomics received a €2.5 million grant to support development and prototype validation from the European Innovation Council Accelerator programme, with access to up to €15 million of equity investment to help prepare for commercial production.

In September 2026, Turkey's Ministry of Energy and Natural Resources made an agreement with Copenhagen Atomics to jointly develop the use of thorium in nuclear technology, aiming to develop domestic production of thorium compounds. Turkey has large reserves of thorium, as of 2026 the sixth largest of identified global thorium resources.

In 2026, the planning was to submit the application for the nuclear test facility by the end of 2026. The first chain reaction tests would take place not earlier than 2028. Commercial deployment was forecast to be about 2030–2031.

As of 2026, alongside the reactor-development program, the company had four commercial products and services for laboratories and other reactor developers: molten salt test loops, specialised salts, enriched lithium isotopes and testing services. The company is raising capital to support development toward the planned 2028 first chain reaction tests.

Reactor design

The company describes its reactor core as shaped like an onion, with the outermost layer being a breeding blanket of 2,000 liters of Lithium Fluoride /Thorium Fluoride salts at 600°C used to transmute thorium into fissile Uranium-233.

The next layer consists of heavy water at 80°C.

Farther inward is the pumped fuel salt layer, about 200 liters of Lithium 7 Fluoride/Uranium Tetrafluoride, which enters the core at 600°C and exits at 700°C, and serves as both fuel and coolant.

The innermost layer is the moderator, more heavy water at 80°C, with the total amount of heavy water being ~1,200 liters.

The layers are separated by stainless steel, in early versions, but later probably by silicon carbide composites. 2 to 3 centimetres of yttria stabilised zirconia insulate the heavy water from the hot salts.

The design requires that fission products are removed online (while the reactor is operating). Named the Copenhagen Atomics Waste Burner, the reactor's design thermal output is 50 MWt, with an envisaged electricity generating capacity of 20 MWe.

Research and development

Copenhagen Atomics is pursuing a hardware-driven iterative component-by-component approach to reactor development, instead of a full design license and approval approach. Copenhagen Atomics is actively developing and testing valves, pumps, heat exchangers, measurement systems, salt chemistry and purification systems, and control systems and software for molten salt applications.

The company has also developed the world's only canned molten salt pump and are developing an active electromagnetic bearing canned molten salt pump. In February 2026, the molten salt pump completed two years of continuous test operation under high-temperature conditions.

Copenhagen Atomics offers many of their technologies commercially available to the market. This includes pumped molten salt loops for use in molten salt reactor research, as well as highly purified salts for high temperature concentrated solar power, molten salt energy storage, and molten salt chemistry research.

See also

• Molten Salt Reactor Experiment
• Liquid fluoride thorium reactor

External links

• Template:Official website
• Template:LinkedIn page