Netherlands-based Thorizon has said Dutch and French nuclear regulators have agreed to collaborate on a preparatory review of its Thorizon One molten salt reactor project.
The Dutch nuclear safety authority ANVS (Autoriteit Nucleaire Veiligheid en Stralingsbescherming) and the French nuclear safety authority ASN (Autorité de Sûreté Nucléaire) with its technical support organisation, the French Institute for Radiological Protection and Nuclear Safety (IRSN – Institut de Radioprotection et de Sûreté Nucléaire) will comprise a series of joint technical meetings starting this autumn. The aim is to present simultaneously to both authorities the Thorizon One reactor ahead of pre-licence applications expected in both countries at the same time in 2025.
This common preparatory review will seek to:
Understand the specific design of this reactor, its safety approach and associated research and development programme.
Define the scope of the pre-licence applications to ensure focus the assessment resources on the most significant safety challenges of the Thorizon One reactor project.
Thorizon said the review is an important step toward the first deployment of the molten salt reactor. Undertaking the review at an early stage of the development of the Thorizon One design is expected to increase the efficiency of the future pre-licensing applications in both countries.
“The early feedback from both nuclear regulators is invaluable for demonstrating the safety of the Thorizon One reactor, said Thorizon CEO Kiki Lauwers. “This multi-country cooperation will facilitate deploying the reactor in multiple countries in the future…. We are committed to delivering a safe, cost-competitive reactor that contributes to the energy transition responsibly with the lowest possible footprint.”
Thorizon, spun out of NRG, which operates the High Flux Reactor in Petten, is developing a molten salt reactor (MSR), targeted at large industrial customers and utilities. Thorizon aims to construct a pilot reactor system before 2035. Thorizon One will provide 250 MWt of industrial heat, which can be directly used in industrial processes for the chemical industry or hydrogen production. Alternatively, it can produce 100 MWe to provide electricity.
The molten salt fuel adopted by Thorizon uses a combination of long-lived elements from reprocessed used fuel and thorium. The reactor will be able to recycle long-lived waste from existing nuclear facilities. The core is composed of a set of cartridges that is replaced every 5-10 years. Thorizon says this offers additional advantages in terms of safety, time to market and costs.
Currently, France and the Netherlands are committed to recycling their used nuclear fuel, reducing nuclear waste and minimise the need for deep storage. Reprocsssing and recycling service is undertaken by France’s Orano, which will also develop the fuel for the Thorizon One reactor.
Thorizon said the project falls under the memorandum of understanding signed in September 2023 between the ASN and ANVS, aimed at collaborating on regulatory initiatives, including the licensing of nuclear installations such as small modular reactors (SMRs), and sharing experiences on new and innovative technologies.
In April 2023, the Ministries of Economic Affairs of France and the Netherlands signed a pact to collaborate on innovation and sustainable growth, including nuclear technology, to strengthen public-private cooperation around concrete projects.
Invest-NL, the Dutch National Promotional Institute, is a shareholder of Thorizon. The reactor project, in consortium with Orano, received a €10m ($11m) grant from the French State under the France 2030 “innovative nuclear reactors” investment plan.
Thorizon aims to develop small modular reactors by the 2030s, envisioning the first molten salt reactor in Europe to be operational by 2032. To streamline the licensing process, Thorizon One plans to comply with existing safety regulations, use licensed materials and components, and work with experienced companies with existing nuclear licences. Thorizon recently hired two licensing experts: Antoine Claisse, previous licensing manager for the ITER fusion project in France; and Marco Visser, previous licensing manager for the Pallas research reactor in the Netherlands.
