Nuclear: SMR, miniature reactors to better distribute electricity distribution?


While new EPRs should see the light of day in France in 2040 to replace aging reactors, Futura went to learn about other reactor technologies. In the program of this second article, recent small modular reactors that would allow energy decarbonization in many countries: the SMRs, were announced by President Emmanuel Macron in February 2022: between 6 and 14 EPR (European Pressurized Reactor or Evolutionary Power Reactor). ) will be built in 2040, in order to maintain nuclear energy as the main source of electricity in France. These reactors are based on the same principle as reactors in use today: heat is created in the reservoir by nuclear reactions, then extracted by water that is kept liquid at high pressure. This water circulates in a closed loop through the primary circuit, itself in indirect contact with a secondary circuit. It cools in contact with this secondary circuit, transmitting its heat to the water that circulates there. The latter vaporizes and spins a turbine that engages an alternator: electricity is generated! Reduce construction costs by producing modular reactors. Other types of reactors are beginning to emerge, or come back into vogue. So fast neutron reactors could be back in the debate in a few years. And other, much smaller reactors are appearing: SMRs, or Small Modular Reactors. To find out more, Futura met with Jean-Michel Ruggieri, head of the SMR program at the CEA (Atomic Energy and Alternative Energies Commission), and Karine Herviou, deputy director-general responsible for the nuclear safety division of the CEA IRSN (Radiation Protection Institute). and Nuclear Safety). It looks a lot like our current reactors, but as the name suggests, SMRs are much smaller. “To give us an idea, an EPR produces between 4,500 and 5,000 thermal megawatts, while an SMR is more than 500 thermal megawatts,” explains J.-M. Ruggieri. “The IAEA (International Atomic Energy Agency) already lists 70 projects available on its site,” says K. Herviou. Some are already in advanced stages, especially in Russia, where the first floating SMRs saw the light in 2020, or in the United States, where the Nuscale reactor received design approval, among them, one especially calls out to us the Attention: Nuward, for “Nuclear Advance”. Officially announced in 2019 by EDF, its principle is the same as a conventional reactor, but smaller! “An SMR, like any nuclear reactor, consists first of all in a boiler block that produces heat, explains J.-M. Ruggieri. Except it’s 5 to 10 times smaller, so it creates even less energy than a conventional reactor. And Nuward will work just like the PWRs (pressurized water reactors) currently used in France, with pressurized water to slow and moderate the neutrons emitted from the ship. A project that should see the light of day in ten years. “Nuward’s goal is to place the first concrete in 2030, but the precise location has not yet been determined. After that, other SMRs will follow, potentially in France but not only,” explains J.-M. Ruggieri, because the term “modular” means that these small reactors could be assemblies of spare parts, themselves built in the factory. Therefore, these reactors could be “produced in series”, explains K. Herviou, although there are still design questions , especially at the level of the steam generators. “The technical particularity of the design is often found at the level of the reactor boiler: Nuward’s goal is to integrate all the elements of the primary circuit in the vessel. We are talking about an integrated concept. This therefore includes steam generators (SGVs) which are, in the case of power PWRs, larger than the ship itself, so the challenge is to miniaturize them: for Nuward, we started with generators of plate steam that required dedicated technological development”, explains J.-M. Ruggieri. Decarbonize energy in countries that still use coal plants. In the future, these reactors. it could be perfectly integrated, without replacing those that already exist. “The main objective of these reactors is to decarbonize energy production, and in particular for industry. Finally, it will be necessary to replace coal and gas with other low-carbon energy sources: solar, wind, biomass and nuclear”, explains J.-M. Ruggieri. Thus they would be added to the energy mix, but not exclusively. “SMRs would not only be used to generate electricity from nuclear energy, but could also contribute directly to producing heat for district heating, or even hydrogen, using electrolyzers. “These small reactors could also be deployed in places that cannot accommodate large power plants, or old coal-fired power plants, whose power is often around 300 MWe, equivalent to that of SMRs. Because of their small size, the costs will also be lower, allowing “countries that cannot have a large power plant to have access to carbon-free energy,” explains J.-M. Ruggieri. “In total, more than 3,000 coal-fired power plants must to replace nuclear-prone countries. Ideally we would replace them by 2040, so that gives us a good depth of market. There are still questions of security, in addition to those of design, as Karine Herviou explains. “Many consider that low power equals lower risks, therefore lower safety requirements. At the IRSN, on the other hand, we ask for security equivalent to that of power reactors. »
#Nuclear #SMR #miniature #reactors #distribute #electricity #distribution


Please enter your comment!
Please enter your name here