France’s Alternative Energies & Atomic Energy Commission (CEA) has launched two start-ups – Hexana and Stellaria. They will rely on CEA’s technologies and patents to develop fourth generation advanced modular reactors (AMRs).

Hexana is looking to design a fast neutron and sodium heat transfer reactor type, incorporating a high temperature storage device. This installation comprises two small 400 MWt reactor units supplying a heat storage device. It will be able to cater for the variations in electrical power required by manufacturers. An adjoining conversion system will allow it to generate electricity if necessary and flexibly to compete with gas power plants. It will also be able to directly supply heat to energy-consuming industries nearby. This will enable those industries to capture CO2, as well as to produce steam, hydrogen and synthetic fuels.

CEA said fast neutron and sodium heat transfer reactors “are of major interest in nuclear material management”. They can operate using mixed oxide (mox) fuel (depleted uranium mixed with reprocessed plutonium. These reactors will support energy sovereignty and reduce high-level nuclear waste through closing the nuclear fuel cycle.

Stellaria aims to develop an energy system based on a chloride molten salt reactor. This technology integrates the fuel in liquid form, dissolved in molten salts which also constitutes the coolant. Liquid fuel can remain almost continuously in the reactor core. Its main advantages are in the combination of energy production and multi-recycling of fuel with a high level of passive safety by design.

The reactor proposed by Stellaria will be very compact measuring 4 cubic metres and will produce 250 MWt. It will be able to use a diversified range of nuclear fuels including uranium, plutonium, mox, minor actinides, and even thorium. CEA said it fits perfectly into the French strategy of closing the fuel cycle.

CEA intends to find partners beyond the nuclear sector for these start-ups, which will be able to apply for government funding.

As part of the France 2030 investment plan, the government recently launched the first call for projects aimed at developing new technologies within the nuclear energy sector. The €500m programme will support new comprehensive concepts of innovative nuclear reactors in the fields of fission and nuclear fusion and is open until 28 June.

The new reactor concepts must allow the introduction of disruptive innovations in research and development in the French nuclear sector in order to:

  • develop the combined production of electricity, heat or hydrogen;
  • promote the closure of the nuclear fuel cycle;
  • improve the management of radioactive waste, by allowing the reduction of its volume or activity; and
  • improve the competitiveness of the energy produced, nuclear safety and security.

This first call is aimed in particular at emerging players who have the ambition to create a new ecosystem of nuclear start-ups, to complement sector leaders. To support these new actors in the development and implementation of their projects, the government says it entrusts CEA to support them with scientific and technical expertise.

Images: Left – The Hexana start-up team: Paul Gauthe, Jean-Baptiste Drouin & Sylvain Nizou; Right – The Stellaria start-up team: Guillaume Campioni, Lucas Tardieu & Nicolas Breyton (courtesy of CEA / L Godart)