Skip to main content
Move the World.
Small Modular Reactors

Lead Image Courtesy of NuScale Power

Nuclear energy is cleaner than fossil fuels, and a single plant can output a tremendous amount of power — two characteristics that could make it a game changer in the fight against climate change.

But building a new nuclear power plant requires a lot of time and money (upwards of $10 billion and 7 years), and nuclear accidents have soured many people on nuclear power. Additionally, while nuclear doesn't create air pollution or carbon emissions, it does produce small quantities of radioactive waste that must be stored.

All that adds up to a nuclear power industry that's on the decline in the U.S. — but small modular reactors could breathe new life into it.

Small Modular Reactors

Nuclear power plants generate electricity by splitting atoms to release energy. This process (nuclear fission) takes place inside a device called a reactor.

One reactor typically produces about a gigawatt of power, and each of the U.S.'s 59 nuclear power plants houses one to three reactors.

As the name implies, small modular reactors are compact versions of traditional nuclear reactors that are designed to be built mostly off-site.

"The vision is that you'd be able to mass manufacture them the way Boeing makes airplanes, put them together as much as possible in a central location, and then ship them out worldwide," nuclear engineer Leslie Dewan explained to Freethink in 2016.

At the time, she also noted that NuScale was making "really great strides on the small modular reactor front" — now, the company's design just became the first to receive a safety certification from the U.S. Nuclear Regulatory Commission (NRC).

NuScale's Nuclear Reactors

Each of NuScale's small modular reactors is 76 feet tall, 15 feet wide, and capable of producing 50 megawatts of electricity. That's just 5% as much power as traditional nuclear reactors, but the company anticipates a typical plant having about a dozen of them.

The design is simpler than that of a traditional reactor, with a passive safety system that the NRC determined would "ensure the nuclear power plant would shut down safely and remain safe under emergency conditions, if necessary."

"You'd be able to mass manufacture them the way Boeing makes airplanes."

Leslie Dewan

A passive safety system means the reactors shut down if they aren't continuously supplied with power. This is unlike the active system at Fukushima, which required power or backup generators to keep the reactors cool.

In theory, it should cost less to build NuScale's small modular reactors on an assembly line, instead of creating unique systems for every plant. And because the design is simplified and standardized, new nuclear power plants should take less time to build and get approval — but it's still not certain.

Still, now that NuScale's small modular reactors have cleared the safety hurdle, the company can start looking ahead and working with customers willing to take a chance on this new approach to nuclear power.

We'd love to hear from you! If you have a comment about this article or if you have a tip for a future Freethink story, please email us at [email protected].

Up Next

Challengers
Dr. Leslie Dewan on the Future of Nuclear Energy
Dr. Leslie Dewan
Challengers
Dr. Leslie Dewan on the Future of Nuclear Energy
We dive into the viability and future of nuclear energy in the U.S. and around the world with Leslie Dewan, CEO of...
By Mike Riggs

We dive into the viability and future of nuclear energy in the U.S. and around the world with Leslie Dewan, CEO of nuclear power startup Transatomic.

Clean Energy
Open-Sourcing the Blueprints for a Nuclear Power Plant
nuclear power plant
Clean Energy
Open-Sourcing the Blueprints for a Nuclear Power Plant
The Energy Impact Center has open-sourced nuclear power plant blueprints in an attempt to encourage the adoption of eco-friendly nuclear energy.

The Energy Impact Center has open-sourced nuclear power plant blueprints in an attempt to encourage the adoption of eco-friendly nuclear energy.

Challengers
Can This Startup Power the World With Nuclear?
Can This Startup Power the World With Nuclear?
Challengers
Can This Startup Power the World With Nuclear?
Leslie Dewan and her team at Transatomic believe they've figured out a safe, scalable, cost-effective way to power...
By Mike Riggs

Leslie Dewan and her team at Transatomic believe they've figured out a safe, scalable, cost-effective way to power the world with nuclear.

Challengers
Three Reasons We Don't Have More Nuclear Power in the U.S.
Three Reasons We Don't Have More Nuclear Power in the U.S.
Challengers
Three Reasons We Don't Have More Nuclear Power in the U.S.
Many think of Chernobyl and Three Mile Island when they hear nuclear power. But nuclear's struggle to gain a...
By Freethink Team

Many think of Chernobyl and Three Mile Island when they hear nuclear power. But nuclear's struggle to gain a foothold in the U.S. is more nuanced than isolated safety problems.

Challengers
Four Crazy Ideas From the Golden Age of Nuclear
Four Crazy Ideas From the Golden Age of Nuclear
Challengers
Four Crazy Ideas From the Golden Age of Nuclear
For a couple decades people thought nuclear power was the answer to pretty much everything. And they came up with...
By Mike Riggs

For a couple decades people thought nuclear power was the answer to pretty much everything. And they came up with some ideas we’ll generously call visionary.

Challengers
Powering the World With Nuclear
Powering the World With Nuclear
Watch Now
Challengers
Powering the World With Nuclear
Transatomic believes they've figured out a safe, scalable, cost-effective way to power the world with nuclear.
Watch Now

Transatomic is designing a nuclear reactor that can produce a lot more electricity than a conventional reactor, while creating a lot less nuclear waste. But they’ll need to take on a deeply entrenched industry and convince a cautious public that they can safely harness the most powerful energy in the world.

Clean Energy
New Solar Cells Could Be a Breakthrough in Clean Energy
solar cells
Clean Energy
New Solar Cells Could Be a Breakthrough in Clean Energy
Better solar cells are an objectively good thing. Two new breakthroughs may help us harness more light, more cost effectively.

Better solar cells are an objectively good thing. Two new breakthroughs may help us harness more light, more cost effectively.

Dispatches
A Zero-Carbon Gas Power Plant Just Came Online in Texas
A Zero-Carbon Gas Power Plant Just Came Online in Texas
Dispatches
A Zero-Carbon Gas Power Plant Just Came Online in Texas
Hey, it works!
Solar Energy
24/7 Solar Power is On The Horizon
solar power
Solar Energy
24/7 Solar Power is On The Horizon
Researchers at the Air Force Research Laboratory are planning new solar power tech that collects energy in outer space and laser-beams it back to Earth.

Researchers at the Air Force Research Laboratory are planning new solar power tech that collects energy in outer space and laser-beams it back to Earth.