Transatomic Power is developing a molten salt reactor. They are using a zirconium hydride moderator instead of graphite. They also use a different salt.
This enables a higher energy density than the 1960s molten salt reactor and a smaller reactor which can be made more cheaply.
They believe with relatively traditional manufacturing methods they can make it at two thirds the cost of current nuclear power plants and make it even cheaper with modular designs. They believe electricity costs from their reactors will be cheaper than coal power.
They can burn low enriched uranium that is almost natural uranium and they can burn waste fuel from existing reactors. 270,000 tons of highly radioactive waste fuel that exists today can be used to power the world for 72 years.
The United States has set aside a $32 billion trust for a repository and has 64,000 tons of SNF to store – approximately $500 per kilogram of SNF. However, our country has not been able to agree on a location or final design for the repository.
Should the USA build a reprocessing facility? The cost to reprocess as the French do is likely $1,000 to $2,000 per kilogram of heavy metal, which is well above what is available in the U.S. Waste Disposal Trust Fund. Meanwhile, SNF can be held inside existing wet storage pools at near-negligible cost. As pools fill up, SNF older than 3-10 years can be placed in dry casks for roughly $100 per kilogram and stored for 40 years or longer, making this method a cost-effective stopgap. About one-quarter of US SNF has been loaded into dry-casks. The other 48,000 tons remain in wet pools, adding to the plant inventory of radionuclides.
The TAP reactor can use fresh uranium fuel or SNF. Utilities can currently only buy fresh uranium from commercial suppliers. The business case for a utility using SNF is somewhat more complicated, because the SNF requires additional handling costs as compared to fresh fuel. A company would need to (1) transport and receive the radioactive spent fuel rods, (2) remove the cladding physically, and (3) dissolve the uranium oxide into the molten salt or convert it to a gas that can be injected into the molten salt. The techniques are well known because the same three initial steps must be employed in reprocessing plants such as at La Hague in France or similar facilities existing at the Idaho National Laboratory . We avoid, however, all of the remaining chemical steps that are the main cost drivers of the work. If full reprocessing costs over $1000 per kilogram, we could potentially perform just the initial three steps for a fractional amount, perhaps in a small number of regional facilities that ship fuel directly to TAP reactors. Our initial assessment is that a disposal charge of $500 per kilogram of SNF is achievable, affordable, and less expensive than reprocessing and would be within the budget allowed by the U.S. Waste Disposal Trust Fund.
The existing 64,000 tons of SNF contain an enormous amount of energy. If all U.S. light-water plants were replaced tomorrow by TAP reactors, it would still take 350 years to consume all of the existing SNF. Even if we expand the role of nuclear by also converting all coal plants to TAP reactors, we could still run for 150 years.
There are a range of commercial power plants that can be envisioned using Transatomic Power’s technology. We worked with Burns & Roe, an experienced nuclear engineering, procurement, and construction firm, on a system-wide pre-conceptual plant for a 550 MWe (gross generation) TAP reactor, with a net output of 520 MWe. Such a plant would serve a gap in the market – today’s most modern light-water reactors are typically large units aimed at 1000 MWe and above; a recent push to develop small modular reactors (SMRs) is aimed primarily at 300 MWe and below. The 520 MWe size may be particularly attractive to utilities because it is sized similarly to aging coal plants. The overnight cost for an nth-of-a-kind 520 MWe size, including on-line fission product removal and storage, was estimated at $2.0 billion with a 3-year construction schedule.
When running on fresh fuel, the TAP reactor is able to generate up to about 75 times more electricity than a light water reactor per kilogram of natural uranium ore