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Energy Department Funds Two Advanced Nuclear Programs

Two companies will receive $80 million from the federal government to build molten-salt reactors and pebble-bed reactors by the mid-2020s.
January 21, 2016

In the latest sign of the U.S. government’s determination to help push nuclear power technology beyond conventional reactors, the Department of Energy is providing $80 million in funding to two advanced reactor programs. At $40 million each in matching funds over the next five years, the grants will go to X-energy, a little-known Maryland-based startup that is developing a new version of a pebble-bed reactor, and to Southern Company, the Atlanta-based utility that is working with TerraPower on molten-salt reactors.

The new funding builds upon the November launch of a DOE-led program to support advanced reactor development and offer a pathway to licensing with the Nuclear Regulatory Commission (see “White House Strikes a Blow for Advanced Nuclear Reactors”). A range of proposed advanced reactor designs are under development. They include machines that use molten salt as both the coolant and the fuel source, ones that run on the radioactive element thorium, rather than uranium, and novel fuel designs such as pebble bed reactors.

It’s a promising development for the advanced nuclear industry, which has struggled to find funding and regulatory approval. Much of the money raised so far has gone to just two companies, Tri Alpha Energy, which is working on fusion reactors, and TerraPower.

X-energy was founded in 2009 by Kam Ghaffarian, who previously founded Stinger Ghaffarian Technologies, a major contractor for NASA. Based in Greenbelt, Maryland, the company is working on a high-temperature reactor that is cooled by gas, rather than water, and uses small fuel particles inside graphite spheres (called “pebbles”), rather than solid fuel rods. The design, says Pete Pappano, the company’s vice president of fuel production, makes the reactor immune to meltdowns. Encased in layers of carbon and ceramics, the individual fuel particles, each the size of a poppy seed, maintain their integrity at temperatures of 1,800 °C, far beyond the temperatures that might be reached inside the core in the event of an accident, according to tests at Oak Ridge and Idaho national laboratories.

Pappano says the company will use the new funding to demonstrate the reactor’s safety features, develop the simulations and supporting materials for NRC licensing, and seek additional private sector funding. It will no doubt need it—it plans to have a reactor up and running by the late 2020s, long after the DOE funding has run dry.

Southern Company, the second DOE funding recipient and one of America’s largest utilities, generates about half its electricity from natural gas and also operates dozens of coal plants across the Southeast. It is already building the first new nuclear reactors to be licensed in the U.S. in more than a decade, at the Vogtle Generating Station in Georgia. One of the few large utilities actively pursuing next-generation nuclear power, the company is working with TerraPower and Oak Ridge National Laboratory to develop reactors that use molten chloride as both coolant and the medium for the fuel, rather than solid fuel rods (see “TerraPower Quietly Explores New Nuclear Reactor Strategy”).

Southern plans to build a prototype of the molten chloride reactor by the mid-2020s. Coupled with recent private funding announcements for companies including Terrestrial Energy and Transatomic Power, the DOE’s support could help jump-start a sector that promises to make real the long-awaited renaissance of nuclear power (see “Advanced Nuclear Startup Terrestrial Energy Lands Initial Funding”).

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