100 MW Factory Made Small Modular Reactor from ARC

Advanced Reactor Concepts (ARC) is a firm based in Reston, Virginia. ARC intends to factory-build a 100 MW sodium cooled fast reactor which has already been proven at the Argonne National Lab West in Idaho. More from Idaho Samizdat Nuke Notes (from an entry in the 7th Carnival of Nuclear Energy):

Getting power out of the reactor

The inlet temperature, according to a specification sheet, is 355 degrees C. The outlet temperature is 510 degrees C. The outlet temperature is what is made available to the balance of plant. The reactor immersed in ambient pressure liquid sodium. The intermediate loop is also liquid sodium.

Transfer of heat to a turbine is being developed to use to Brayton Cycle which uses liquid CO2 yielding an expected 40% efficiency rate for heat transfer. However, Ali said the company is also working with turbine manufacturers to develop steam applications.

Answer on nonproliferation issues

In an answer to critics of nuclear energy who worry about bomb makers, Ali points out the fuel for the ARC-100 is sealed in the reactor, used for 20 years, and then returned to the factor, or a regional fuel center, for reprocessing. The customer doesn’t touch the fuel, stores any on-site, or manages the used materials.

“The customer never has access to the fuel.” Ali said.

According to the first phase design information provided by the company, the “fuel cartridge” is inserted in an underground portion of the reactor. There are no safety-related systems in the balance of plant. The reactor vessel installed underground and is 15 meters high with a diameter of about 7 meters. See conceptual image left.

The fuel itself is enriched to an average of 14% depending on customer requirements. The specifications for the fuel are found in a database developed for the EBR-II reactor which means extensive first-of-a-kind fuel testing required for some of the other fast reactor SMRs won’t be needed for the ARC-100.

“It is a proven metal-alloy fuel,” Ali said.

On the reprocessing side of the fuel cycle, creating new fuel for the ARC-100 does not involve separating pure plutonium that could be used in nuclear weapons. Instead, it keeps the plutonium mixed with other long-lived radioisotopes so that it cannot be used in making bombs.

Next steps

Ali said the company is now holding “pre-application discussions” with the NRC ahead of formally submitting the reactor for design certification. Ali did not indicate a date when the firm would formally submit a package to the NRC. _ISNN

White paper on ARC-100 at Google Docs

A pre-loaded nuclear fuel cartridge that provides reliable power for 20 years between cartridge changes goes a long way toward providing optimal safety and confidence in a power source.

This article from Idaho Samizdat was featured in the 7th Carnival of Nuclear Energy. Another article featured in the same carnival which is a very useful expansion of the above Idaho Samizdat article can be found at Capacity Factor. The Capacity Factor article also looks at competing designs for liquid metal fast reactors.