ARC-100 Reactor


With worldwide demand for electrical power expected to double over the next 25 years, the world faces the daunting challenge of providing affordable electricity to an expanding population without exacerbating climate change or fostering nuclear proliferation. Advanced Reactor Concepts, L.L.C. (ARC) will address this challenge. ARC is developing an exportable, factory-produced, 100 MWe nuclear reactor with fixed fuel costs for 20+ years.

The ARC-100 design creates a "walk away" passive safety system that insures the reactor will never melt down even in a disaster that causes a complete loss of power to the plant site. In addition, it can be fueled with the nuclear waste produced by traditional reactors, and its 20 year refueling cycle offers new levels of proliferation resistance. It provides a new model for nuclear power that is based on factory fabrication of modular components that can be shipped for rapid site assembly, thereby promoting the prompt start of a revenue stream.

The reactor's basic technology was proven through the successful 30 year operation of the EBR-II prototype (described below). ARC has made significant proprietary advances to the original EBR-II design in order to create the ARC-100.

Sodium Fast Reactor Basics

A Simple, Inherently Safe Design, Operating at Atmospheric Pressure, Yields Lower Plant Cost

Image courtesy of Generation IV International Forum (


ARC-100 Advantages

Sodium as Coolant

The use of sodium instead of water as the heat transfer agent in the reactor allows the reactor to operate at ambient pressure. Its containment vessel is a double walled stainless steel tank rather than a 12 inch thick forged steel containment vessel required for traditional light water reactors.

Re-Use of Nuclear Waste

The ARC-100 can be used to recycle traditional nuclear waste and generate energy, burn or transform plutonium that could be used for weapons and eliminate the need to bury or store large quantities of nuclear waste.

Small Size

Small enough that its modularized components can be shipped and installed at the site using regular commercial equipment, such as barges, rail, trucks, and construction cranes.

Passive Safety

Effectively "walk away" fail safe and protection of the reactor from a melt down does not depend on extra pumps, operator intervention or any external system in the event a disaster destroys all electric power to the plant site.

Twenty Year Refueling Cycle

The proprietary reactor core of the ARC reactor is designed to operate for 20+ years without refueling.


Experimental Breeder
Reactor-II (EBR II)


The protype for the ARC-100 reactor is a reactor known as the EBR-II. The EBR-II was operated by the US government's Argonne National Laboratory in Idaho for 30 years as a very successful test and demonstration sodium-cooled fast-reactor power plant. As a complete power plant, the reliability of the system was demonstrated, and sodium operating and maintenance technology was established. As an irradiation test facility, Oxide, Metal, Carbide and Nitride fuels were developed. Oxide fuel for the FFTF and CRBRP was qualified and Metal fuel was extensively developed for EBR-II. As an operational-safety test facility, the self-protecting response of a metal-fueled reactor was demonstrated for Anticipated Transients without Scram and the benefits to safety were quantified in a PRA. The safety of operation with breached fuel was also demonstrated. As the Integral Fast Reactor (IFR) prototype, proliferation-resistant reprocessing and recycle of fuel was demonstrated and fuel containing minor actinides was fabricated and irradiated. When decommissioned, draining and reaction of the sodium to produce an acceptable form for disposal was accomplished, including passivation of residual sodium. Waste forms for geologic storage of waste from fuel reprocessing were developed and qualified. The EBR-II experience and test program has established the viability of sodium-cooled fast reactor power plants.

Learn more about the EBR II—and the Integral Fast Reactor that followed it—in this YouTube clip from Robert Stone’s award-winning 2013 documentary Pandora’s Promise, a feature-length film about the history and future of nuclear power.

The primary presenter in this video is Dr. Charles E. Till, who headed up the major effort in the US at Argonne National Lab to fully develop and advance sodium fast reactor technology.

For more on Pandora’s Promise, and to watch the complete film, please visit their official site: