ThorCon Advanced Nuclear Reactor -- More Than Worth Its Weight In Salt
It’s been 30 years since America built a really new nuclear power plant, but we haven’t been idle over this time. A slew of new designs have emerged and, thanks to advances in computing capabilities and the understanding that smaller is better, many of these are ready to be built economically.
This is important. Over the last several years, there has been a growing consensus among climate scientists that nuclear energy is critical for mitigating the worst effects of global warming. States are shifting from Renewable Energy Mandates to technology neutral Clean Energy Standards that include nuclear energy.
So it is good that the development of new nuclear technologies is speeding along faster than most people think. Many new nuclear start-up companies have emerged in the United States, China and Canada, especially those designing small modular reactors (SMRs).
Importantly, all are walk-away-safe, which means the reactor just won’t melt down or otherwise cause any of the nightmares people think about when imagining the worse for nuclear power. It just shuts down and cools off.
Canadian Nuclear Laboratories announced SMR technology as a research priority and Canada now has a roadmap for them, and has vowed to build an SMR demonstration plant on their site by 2026.
China is also moving fast on its Linglong One 100 MW SMR with its first use to generate heat for a residential district, replacing coal-fired boilers.
While some SMR designs are based on the traditional light water reactor that uses slightly enriched uranium, others involve molten salt and other fuels such as thorium and thorium+uranium.
One such reactor is ThorCon, a fission reactor with a liquid molten salt fuel containing thorium+uranium. A full-scale 500 MW ThorCon prototype should be able to be built and operating within four years.
Molten salt reactors are not completely new. The United States successfully conducted a Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory in the 1950s.
Irradiation tests on a mixture of lithium and thorium fluoride salts are under way at the High Flux Reactor at Petten in the Netherlands. Terrestrial Energy is also developing an Integrated Molten Salt Reactor.
But the ThorCon takes a different tack on manufacturing. It would be completely manufactured in 150 to 500 ton blocks in a shipyard, assembled, then towed to the site, producing order of magnitude improvements in productivity, quality control, and build time.
ThorCon’s genesis is in ship production, one of the few industries up to snuff for building large complicated technologies. The Hellespont Fairfax, the largest double hull tanker ever built, is one of eight ships built by ThorCon’s predecessor company. She was built in less than 12 months and cost 89 million dollars in 2002.
ThorCon is designed to bring shipyard quality and productivity to fission power. But ThorCon’s structure is simpler and much more repetitive than a large ship. The fission island employs steel plate, sandwich walls filled with concrete or sand. This results in a strong, air-tight, ductile building, all simple flat plate. A properly implemented panel line will be able to produce these blocks using less than 2 man-hours per ton of steel.
Each ThorCon plant is based on one or more hulls, each containing two 250 MWe power modules, a 500 MW super-critical turbogenerator, gas insulated switchgear (GIS), a decay heat pond, and auxiliaries (see figure above). The fission island is at the forward end of the hull. Aft of the fission island is the Steam Generating Cell (SGC). Aft of the SGC is the turbine hall, which contains the turbogenerator, exciter, condensers, feedheaters, pumps, and condensate treatment.
Bookmarks