illustration of Thorcon 500 prototype power plant at Kelasa Island, Indonesia

The plan for introducing liquid fission power to Indonesia has two parts. Phase 1 is to build and test a 500 MW Thorcon 500, with step by step commissioning, ending in an approved type license for future power plants. Phase 2 is shipyard production of six Thorcon 500 plants to help Indonesia’s utility company provide an additional 3 GW of cheap, reliable electric power to support economic development.

The conceptual design phase has been completed, computationally modeled, expressed in 2D drawings and 3D CAD models, and shared with potential suppliers. Suppliers’ cost estimates for future production versions are compatible with company estimates of electricity production costs, well under those from coal-fired power plants.

The 500 MW power plant will be built in a world-class shipyard experienced in high-quality, cost-competitive steel-working. ThorCon will rely on the yard for detailed design outside the Can, production scheduling, and much of the equipment purchasing functions. The shipyard will be ThorCon’s EPC (engineering, procurement, construction) contractor. The expensive, massive, precision supercritical steam turbine-generator must be pre-ordered to achieve the one-year shipyard build time.

The shipyard will construct and outfit the two hulls that comprise the Thorcon power plant. These are the steam module containing the supercritical steam turbine generator, and the nuclear module with two power modules, each with two replaceable Cans. The nuclear reactor Pots are in the Cans, which will be fabricated by companies with nuclear industry experience.

Non-fission testing. The first nuclear module produced by the shipyard will be outfitted with a Can for nonfission testing, without enriched uranium in the fuel salt. Electrically powered resistance heaters are sized to heat components up to operating temperatures.

The fuel salt will not contain enriched uranium and will not sustain a chain reaction to generate power. The components will be brought up to operating temperatures using electric heating. The absence of radioactivity allows intrusive instrumentation, direct observation, and internal access to components.

Extensive testing will include operating pumps at full temperatures and pressures, drains to drain tanks, actuation of shutdown rods, and instrumentation. Motors, pumps, seals, and valves for molten salt flows will be tested. Engineers will measure thermal expansion, confirm heat transfer rates, verify thermal hydraulics characteristics, test sensors, transfer molten salts between the Pot and fuel casks. System responses to simulated failures will be monitored closely.

If testing reveals needs for changes, the nuclear module and/or Can will be returned and revised by their manufacturers. Thorcon 500 prototype power plant at Kelasa Island, Indonesia

Fission testing. The ThorCon 500 nuclear module and steam module will be towed to the Indonesia near-shore site prepared with breakwaters and seawater cooling piping and a connection to the PLN electric power grid.

Step-by-step commissioning will then be used to gradually reduce uncertainties and increase fission power levels. Working closely with Indonesia’s nuclear regulator (Bapeten) and expert test approvals committee (TAP), ThorCon engineers will proceed with step by step commissioning, fueling the plant, bringing the reactor to zero-power criticality, then increasing power levels as testing confirms safe, effective power generation.

Stress tests. ThorCon is designed to react safely to many operational events and failures. Demonstrating safety is important to public acceptance of fission power. Test examples include sudden loss of load, overheating the fuelsalt, losing chimney radiator cooling, and failure of shutdown rods. These tests are possible because of multiple layers of defense in the design. The TAP must pre-approve all such tests, continuing the step by step commissioning process.

Mass production. When testing is successfully completed, the company expects Indonesia’s Bapeten regulator to refine its regulations and issue a type license citing the design as safe for similar future power plants. Indonesia’s PLN utility company will sign a power purchase agreement (PPA) with Thorcon, which will build, install, and operate 3 GW of additional Thorcon 500 power plants. The PPA will enable financing with traditional loans. As these plants are put into operation the company expects world-wide orders for such shipyard-constructed power plants that deliver nonstop electric energy cheaper than coal.