Seaborg completes experiments to optimize its molten salt reactor design
The Danish nuclear reactor company Seaborg Technologies is currently carrying out important experiments in collaboration with experts from the Neutron and Muon Source (ISIS) in Oxford (Great Britain) and the European Spallation Source (ESS) research center in Lund, Sweden. The aim is to understand how neutrons behave in modern reactors. The new findings should enable Seaborg to optimize their reactor design. The company aims to put its first reactor online by 2025. Seaborg develops compact Molten Salt Reactors (MSRs).
The company reached a major milestone in early summer when one of the salts was tested as a neutron moderator. The moderator slows down the neutrons that trigger the chain reactions. If the neutrons move too fast, the probability of a fission reaction decreases, so that the reactor shuts down or stops completely. The experiment at the ISIS neutron and muon source is important because it confirms how neutrons behave in Seaborg’s moderator.
The co-founder and reactor physicist Dr. Esben Klinkby said the collaboration with the experts from ISIS and ESS was “tremendous”. He added, “We obtained extremely accurate measurements from this. The analyzes have not yet been completed, but I can already say that the data seem to confirm our expectations of the good moderating properties of NaOH. “
The MSR was originally developed in the US in the 1950s and 1960s, but the project was discontinued and never commercialized due to severe technical challenges with the moderator that could not last more than four years in the harsh environment. Seaborg has a proprietary type of liquid moderator that is also based on molten salt – NaOH (sodium hydroxide), which is itself a highly caustic base that is often used as a drain cleaner. The NaOH has great properties as a moderator. One advantage of NaOH as a moderator over graphite is that the radiation does not wear the materials over time. As a result, the Seaborg reactor will last 12 years without having to refuel or change the moderator.
The life of the reactor is a crucial factor in judging whether the economics of the molten salt reactors are good or not. For Seaborg, the goal is to become price competitive with fossil fuels, for example in Southeast Asia, where strong financial growth and geographic conditions make renewable energies unfavorable.
With the data from the experiments, researchers from Seaborg and ESS can create a computational model that shows how much the moderator slows down the neutrons in the reactor. For Seaborg, the experiment is a key factor in optimizing the reactor design and an important part of the regulatory process.
The company is developing an inherently safe 4th generation nuclear Compact Molten Salt Reactor (CMSR) with an essential proprietary moderator. With its uranium-based fluoride fuel salt, the CMSR has several outstanding features; it cannot melt or explode, it cannot release radioactive gases into air or water, and it cannot be used for nuclear weapons.
The CMSR is installed on modular barges and delivers clean and affordable electricity worldwide. The power barge design enables configurations with two, four, six or eight CMSRs delivering up to 800 MWe or 2000 MWt. Two reactors will be installed in the first power barges, which will deliver 2 x 100 MWe for the 24-year lifespan of the power barge. The CMSR Power Barge is competitive whether it is plugged into the power grid in an existing coal port or it produces hydrogen and ammonia.
Seaborg said his goal is to get the CMSR power barge into rapid worldwide deployment via the yard’s serial production. The ambitious plan is for the first CMSR Power Barge to go into operation in 2025. In 2020, the company issued a declaration of feasibility for the CMSR reactor from the American Bureau of Shipping. Seaborg uses the maritime qualification process for new technologies as a cornerstone in the official approval process.
Photo credit: Power Barge (Credit: Seaborg)