You had a lot of questions about next-generation nuclear reactors. We introduce them to the experts

The United States is accelerating efforts to license and build a new generation of nuclear reactors to provide carbon-free electricity.

Faster development is something Congress and the administration agree on. President Joe Biden signed legislation in July to modernize licensing of new reactor technologies so they can be built faster. Republican and Democratic leaders of the Senate environment and House energy committees praised the enactment.

The US is developing small modular reactors and advanced reactors. Some designs use something other than water for cooling, such as liquid metal, helium, or liquid salt. Developers say advanced coolants allow reactors to operate at low pressure, making them safer than traditional designs.

Russia and China are the only countries that already operate advanced reactors.

The United States is trying to push new technology; the Department of Energy announced $900 million in funding in June. Bill Gates’ company, TerraPoweris the first in the U.S. to apply to the Nuclear Regulatory Commission for a construction permit for an advanced reactor that would function as a commercial nuclear power plant.

Readers asked the Associated Press questions about the evolution of nuclear energy. They wonder how the next generation of reactors could be a climate solution, where radioactive waste would go and, most of all, whether these new reactor designs are safe.

The AP turned to the White House National Climate Advisor Ali Zaidi and experts from the Department of Energy and the Nuclear Regulatory Commission to help answer these questions.

Q: Elizabeth M. of Bisbee, Arizona, said advanced nuclear power seems like a compromise that, despite its drawbacks, is the most practical and clean solution to America’s large energy appetite. We asked Zaidi for his opinion on how these new reactors could be a climate solution.

Zaidi said the world must meet future energy needs “in a way that does not increase the problem of climate change”. Nuclear power is one tool that can do that, he said.

“As we find ourselves in the midst of the climate crisis, in the defining decade for climate action, it is up to us to pull out all the tools in the field and help harness these technologies in the race to the future,” said Zaidi.

Nuclear power plants do not emit the planet-warming greenhouse gases that come from plants that burn fossil fuels.

Q: At least one reader wondered about the timeline for these reactors to come online, lamenting how long it takes for older plants to come online.

Zaidi said the US is working hard to make that happen “this decade.” And he said the goal is “a huge increase and expansion of this technology” over the next 10 to 15 years.

The most advanced project, from Gates’ TerraPower, applied for a construction permit in March. The company has said it wants to begin operating commercially in Wyoming in 2030. The NRC has a target of 27 months for its technical review. If the NRC approves the project within that timeline, TerraPower could produce electricity in the early 2030s if it takes about three years to build its plant and obtain an operating license. But that’s not right. Other pioneering nuclear projects have often faced delays and cost overruns.

Q: Many readers – including Jim M. of Manheim, Pennsylvania – wanted to know what would happen to the radioactive waste from the new reactors. The issue arises from the United States decades-long inability to find a place to store spent fuel of current and former nuclear plants across the country. Right now, spent fuel is being stored at more than 70 locations in more than 30 states – enclosed in steel-lined concrete pools of water or in steel containers known as dry storage vats.

Acting Assistant Secretary for Nuclear Energy Michael Goff said spent fuel from the new reactors will be stored in the same locations where it is used — the same situation the U.S. has today — until some federal storage facility is operational.

Goff said spent fuel from any new plants must be “stored, transported and disposed of” to meet the same NRC requirements that govern waste from current plants. This basically means keeping you cool and protected.

The shape and composition of the fuel in some of the new reactors will be different, meaning some technical changes may be needed in the way the fuel is packaged and contained, the Energy Department said.

Goff noted that nuclear fuel can be recycled to produce new fuel and byproducts, saying that “more than 90%” of its potential energy remains even after the fuel has been used in a reactor for five years. The US does not currently recycle any of its spent nuclear fuel, but Goff said other countries, including France, do. And he said some advanced U.S. reactor designs could someday “consume or run on spent nuclear fuel.”

The French nuclear industry reprocesses spent fuel to recover uranium and plutonium for reuse, which reduces the volume of waste. Some radioactive materials, or byproducts, have commercial, medical and academic uses. The United States has studied the prospect of commercial reprocessing of spent fuel, but expected little interest from applicants for reprocessing facilities and does not currently encourage it.

Q: Anne L. of East Bay, California, wants to know if these reactors present the same problems and dangers as large plants. She wasn’t the only reader to wonder about risks like overloads or meltdowns.

Nuclear Regulatory Commission spokesman Scott Burnell said all U.S. nuclear plants must meet NRC safety requirements by showing how they operate safely under normal conditions.

“They must also demonstrate that they can safely shut down and then keep the fuel properly cooled, under normal conditions and in the event of severe weather, earthquakes, problems with power plant systems and other extreme events. Current reactors use pumps and backup power systems to remain safe; new projects can rely on natural processes such as gravity and convection to remain safe,” he said.

Burnell said the latest designs propose nuclear fuels and cooling capabilities that reduce the already small possibility of the fuel overheating or melting. The NRC will require that even these designs take extreme events into account and keep the fuel cool and safe, he said.

___

The Associated Press’ climate and environmental coverage receives financial support from several private foundations. AP is solely responsible for all content. Find APs patterns for working with philanthropies, a list of supporters and areas of coverage funded in AP.org.