Resurgence of nuclear power: Expert available

• For Journalists
• News Releases
• Latest Releases
• News Release

Resurgence of nuclear power: Expert available

'Supply chains are being reestablished and workers trained, but there's still a way to go'

EVANSTON, Ill. - As technology companies race to build energy-hungry AI data centers, they increasingly are turning to nuclear power for the enormous amounts of around-the-clock electricity those facilities require.

This month alone, Google announced agreements tied to nuclear power in Georgia, Iowa and Finland. Meanwhile, the federal government plans to reopen Iowa's shuttered Duane Arnold Energy Center, which follows an effort to revive Three Mile Island Unit 1.

Northwestern University nuclear engineer Elmer Lewis is available to discuss nuclear power's resurgence, the limits of other renewable energy options and what nuclear accidents have taught engineers about reactor safety. Lewis is a professor emeritus of mechanical engineering at Northwestern's McCormick School of Engineering, where he has studied the physics and safety of nuclear systems for more than six decades. He also recently authored the book "Renewables or Nuclear: Which Should Lead in Curbing Climate Change?" (Springer 2026).

To request an interview with Lewis, contact Amanda Morris at [email protected].

Lewis explains how nuclear reactors generate energy:

"It starts with a neutron chain reaction. When a neutron strikes a uranium atom, it splits - a process called fission - and releases energy as heat, along with additional neutrons. Some of those neutrons split other uranium atoms, so the chain reaction keeps going.

"That process produces a tremendous amount of heat. The heat from a reactor ultimately produces steam. The steam spins a turbine, which turns a generator. The generator converts the turbine's mechanical energy into electricity, which then goes out onto the grid.

"So, in that sense, a nuclear power plant isn't that different from a fossil-fuel power plant. Both use heat to produce steam and turn a turbine. The big difference is where the heat comes from. Instead of burning coal or natural gas, a nuclear plant gets its heat by splitting atoms. Importantly, nuclear plants produce millions of times as much energy per pound of fuel as fossil fuel plants do. Moreover, fossil-fuel plants emit copious amounts of the greenhouse gases that cause global warming, while reactors emit none."

On comparing renewables to nuclear energy:

"There are three major issues with wind and solar: intermittency, land use and grid stability. Wind and solar are dilute energy sources, so you need a lot of land. To put the land-use issue in perspective, I did a calculation comparing wind power to two nuclear reactors that supply electricity to the Chicago area. To generate the same amount of electricity with wind, you would need a wind farm covering an area roughly the size of Cook County, which includes much of the Chicago metropolitan area.

"Then there's intermittency. The sun doesn't always shine, and the wind doesn't always blow. During those lulls, other sources of electricity or stored energy must step in to meet energy demand and keep the grid stable."

On safety concerns:

"I think nuclear safety needs to be considered in the context of other risks, such as fossil-fuel air pollution, which causes thousands of deaths each year. Chernobyl was an outlier. It was a poorly designed reactor that would not have been licensed in the West. It lacked a containment structure, and operators were conducting unauthorized experiments under circumstances that led to the accident.

"Fukushima taught us a different lesson. The reactors shut down as the earthquake hit, but radioactive decay continues producing heat after a reactor shuts down. The tsunami flooded the diesel generators that powered the emergency cooling systems, so eventually the heat could no longer be removed from the reactors. Those accidents have influenced newer reactor designs."

On improving safety:

"A major advance involves cooling. Older emergency cooling systems depended on pumps, valves and electricity. Newer designs can use natural convection to remove decay heat. Hot water rises and cooler water falls, creating circulation without needing electrically powered pumps. That means that even if outside electricity is lost, heat continues to be removed from the reactor.

"Reactors also have improved containment structures surrounding them. In the event of an accident, those thick, reinforced barriers prevent radioactive material from escaping into the environment."

On nuclear's challenges:

"Part of it is public opinion, but cost has also been a major issue. For a long period of time, the U.S. did not build new reactors. When construction started again, projects suffered delays and major cost overruns. Part of the problem was that the workforce and supply chain that once supported reactor construction had largely disappeared. So, much of the cost problem wasn't the underlying technology; it was everything surrounding construction. Now supply chains are being reestablished and workers trained, but there's still a way to go."

On small modular reactors:

"Instead of building one enormous 1,000-megawatt reactor, you could build smaller modular reactors - perhaps 300 megawatts or less. That reduces the amount of capital you need to put up at any one time.

"As important, major components can be manufactured in factories rather than constructed individually at each reactor site. If you build enough of them, reactors could become more like airplanes: You build the same design repeatedly in a factory with a trained workforce that doesn't have to move from site to site."