Staff writer

Apr. 5, 2018

EPHRAIM—Ephraim City has made a big investment in a new mode of nuclear power, and the city council learned more about the nuts and bolts of this investment recently.

Councilman Richard Wheeler reported to the Ephraim City Council on March 21 on the progress of the NuScale small module reactor electrical power plant, and why he thinks the project is such a good investment for Ephraim.

Ephraim’s interest in nuclear power began during the Obama Administration, when the federal government decided that new energy generation would have to be “carbon free.”

Presently, coal-fired electrical plants are scheduled to shut down or convert to natural gas by about 2021.

Wheeler said Ephraim realized it would have to have a “backup plan” for when that happened.

Cory Daniels, Ephraim’s Power Department director, said Ephraim invested 3,000 kilowatts of electrical power (or about $72,000 a year) into the new project.

While this may sound like a lot of money, it is only a small percentage of the money needed just to get the project certified and licensed by the Nuclear Regulatory Commission (NRC). Licensing alone is expected to cost $200 million. The plant will cost $3 billion to build and install and will generate 600 megawatts of power.

However, once the project is licensed, the revenues from the new plant should take off.

Ephraim’s investment is estimated to be 0.05 percent of the total revenue generated by the plant.

Wheeler made a “loose guestimation” 0.05 percent of the plant’s revenue to equal between $11,000 to $14,000 per day, or approximately $4-5 million per year. Wheeler said, “With those numbers, it’s a no brainer.”

Ephraim’s return will begin when the new plant is online and begins selling power retail.

Daniels said that would likely be sometime in 2026.

But Wheeler added Ephraim’s investment did not just include the first plant: “It will be 0.05 percent of the project worldwide.” That could turn out to be a whole lot of money.

The Messenger contacted Mariam Nabizad, communications director at NuScale, for technical details on the power plant project.

The small modular reactor design is a result of a project started 18 years ago as a collaboration between Oregon State University, the Idaho National Engineering and Environmental Laboratory and Nexant. The original concept, designated as “Multi-Application Small Light-Water Reactor,” was refined by the university after the conclusion of an initial three-year project and became the basis for the current NuScale design.

Using gravity to produce natural convection circulation of the heat transfer system from the reactor to the steam generation part of the system is a major design victory. This guarantees that, even in the event of total electrical power failure in the system, it will continue to cool the reactor.

Daniels said, “It’s almost impossible for it to fail.” “There’s one chance in 200 million years” is how Wheeler described the possibility of failure of the NuScale plant, which makes it so much safer than the larger nuclear power plants of the past.

The biggest difference between this plant and older plants is all of the functions are designed to shut off automatically if the plant should ever lose electrical power.

Because the plant uses gravity and convection to produce the steam that powers the electric turbine, those very same elements will automatically cool the reactor if there is power loss.

Wheeler described how the plant works: “The plant has zero carbon emissions. By using hundreds of ‘pellets’ (smaller than your little finger) which have been enriched to 5 percent of Uranium-235, the plant can generate heat through boiling water to turn an electric turbine and then cool the water through natural convection.

“The pellets are rechargeable. When they are spent, they are innocuous/do not radiate. The plant can run 40,000 homes at full capacity for two years nonstop. The spent pellets can be stored onsite, which is only 43 acres. The plant does not generate any wastewater either.

Daniels gave an example of how efficient the plant was: “One little nib of uranium [the pellet] is as good as a ton of coal. That’s just amazing.”

Nabizad emphasized the NuScale plant is also safer than previous nuclear plants because it is just smaller than previous models.

Safety is achieved, in part, by reducing the size of the reactor so that even in a worst-case scenario, there is not enough nuclear material to present a significant hazard to the surrounding area. The reactor is 20 times smaller than most similar reactors so there is simply not enough radioactive material to create a danger except in the immediate area (within the power plant installation proper).

Safety is also achieved by extensive simplification of the system.

NuScale’s website states, “The NuScale design eliminates many vulnerable pipes, pumps and valves from the design and replaces many engineered backup systems with features that operate automatically, relying on natural phenomena such as gravity, convection and conduction.”

Nabizad pointed out the differences between NuScale’s small modular reactor plant and the 2011 Fukushima plant’s explosion: “A commercial nuclear power plant cannot explode like a nuclear weapon. First, the nuclear fuel is commercial grade ‘low enriched’ fuel with enrichments below 5 percent of Uranium-235. Second, the U.S. Nuclear Regulatory Commission requires that commercial nuclear power plants be designed with reactor physics that inherently reduce power as the reactor temperature increases. A commercial nuclear core can overheat causing fuel damage, but will not explode like a weapon.”

She explained, “The explosion that was observed [in Fukushima] was the result of the ignition of hydrogen gas as opposed to a nuclear explosion. Hydrogen gas is a byproduct of the nuclear fuel cladding interacting with steam at very high temperatures. Advances in nuclear fuel materials … will greatly reduce or eliminate hydrogen production from this interaction.

“In addition, unlike the reactors at Fukushima, a NuScale nuclear reactor resides within a steel containment vessel that can be pressurized up to around 1,000 pounds per square inch. The containment/reactor vessels are located underwater below ground level. During normal operation, the volume inside the containment is under vacuum conditions so there is little to no oxygen present. Under these conditions, in the highly unlikely event that some hydrogen is produced, it cannot generate a combustible mixture of hydrogen and oxygen inside containment.”

A scale model of the plant is currently on display at Snow College’s Science Building.