Small and Tiny Nuclear Reactors Can Save American Energy - 2021

Nuclear Power Industry

Delbert reported in early 2021 that often touted as a more flexible, powerful alternative to renewables, nuclear’s advantages haven’t outrun its dogged resistance by the uninformed. Delbert claims that she associates nuclear reactors more often with disaster than innovation [Only ignorant people do], but as the United States takes more coal and gas plants offline, engineers are hoping fresh reactor concepts could fully redeem nuclear’s stature in American energy. Bigger is no longer better. The future, experts say, looks like “multispeed” nuclear energy—a combination of traditional large plants and smaller, but safer she claims megawatt reactors [but nuclear power has a safety record exceeding oil and gas, coal, wind, solar, and even hydroelectric].

“Until now, customers only had one choice for nuclear, and that was a gigawatt-sized power plant,” says Rita Baranwal, the assistant secretary for Nuclear Energy at the Department of Energy. “Now, we’re talking about reactors at the megawatt scale that can flexibly meet a customer’s energy needs as demand grows.”Baranwal says megawatt reactors (one megawatt powers about 650 homes) will be cheaper to build and operate, and could be sited anywhere in the world. A more context-sensitive, localized nuclear power industry—in which small towns, remote facilities, and big cities find nuclear solutions tailored to their needs—could replace a large swath of fossil fuel power stations, filling in the inert, resource-sucking downtimes left by renewables.

The tenets of nuclear reactor design can be traced back to Enrico Fermi’s original 1942 reactor at the Argonne National Laboratory near Chicago. Fermi and the other engineers at Argonne proposed and designed many kinds of reactors, like commercial boiling-water reactors and experimental research reactors, says Katy Huff, nuclear engineer and researcher at the University of Illinois at Urbana-Champaign’s nuclear, plasma, and radiological engineering (NPRE) program. Argonne spearheaded a creative boom in nuclear energy. “All these different reactors were conceived at the same time,” Huff says. “At the beginning, we were trying all of them.”

Not every reactor survived. Just as HD DVDs fell to Blu-ray, so did experiments like the sodium reactor at the Santa Susana Field Laboratory and the gas-cooled Peach Bottom plant in Pennsylvania fall to the more commonplace light-water reactor. Even nuclear-reactor designs owe some success to chance, convenience, and market whim.

The ideal reactor by today’s standards emphasizes safety, cost-​effectiveness, and adaptability. Ever since engineer Richard Eckert of the New Jersey Public Service Electric & Gas Co. conceived of a floating nuclear plant in 1969—one that could be built off-site, towed to its final destination, and operated over water—there’s been a vein of thinking in nuclear that says smaller reactors are a suitable form of power for the future. That’s where tiny nuclear hopes to prove itself a competitive alternative to the massive nuclear power plants we know.

Generally, tiny reactors have a few advantages over power plants. First, they are more space-​efficient. A 2019 small modular reactor design from Oregon startup NuScale is about 1 percent the size of a traditional power plant’s containment chamber, though it delivers 10 percent of a plant’s power output. And while traditional nuclear plants need a 10-mile safety buffer in every direction in case of a meltdown, tiny reactors can operate in close quarters with much less risk. That’s the second major edge: safety. Some small reactor designs incorporate fully passive safety and risk-management systems that rely on the steady, immutable laws of physics—like gravity or buoyancy—to perform safety functions rather than the actions of people or mechanical equipment. Finally, there’s scalability. Many small reactors are designed with replicability in mind. If a community, factory, or city needs an extra boost of nuclear power, they can just order another reactor.

NuScale is the most conservative of the small-nuclear programs trying to reach the market. Their reactor design is a traditional light-water reactor, but smaller, simpler, and—according to NuScale—more scalable. The design eliminates coolant pumps, external steam generator vessels, and other equipment found in existing plants, so NuScale claims it’s cheaper to manufacture, lower-risk for operators, and easier to maintain.

The light-water design gives NuScale an edge in power among its tiny-reactor peers. While other companies are seeking approval for reactors that produce just a few megawatts of energy, NuScale’s design reaches 60 megawatts. For comparison, the smallest nuclear plant in the U.S. produces 600 megawatts, yet it's 100 times the size of NuScale's power module. NuScale’s reactor will seek to complement, not replace, a grid already dependent on renewables. During the day, it can operate at 20 percent energy production to let the renewables do the work, before cranking up to 100 percent at night, while the rest of the grid is on solar downtime.

Read on ... outstanding article.