Small Modular Reactors Approval: A Historic Milestone for US Nuclear Energy
The United States has reached a pivotal moment in its pursuit of clean energy. The Nuclear Regulatory Commission (NRC) has officially certified the first design for a small modular reactor (SMR). This approval marks a significant shift in regulatory history, opening the door for a new generation of nuclear technology that promises to be safer, smaller, and more flexible than traditional large-scale power plants.
For decades, nuclear energy meant massive concrete cooling towers and multi-billion-dollar construction projects that took years to complete. The certification of NuScale Power’s design changes that narrative. It signals that regulators are ready to move forward with advanced nuclear solutions intended to help decarbonize the power grid.
The First Certified SMR Design
The NRC issued its final rule certifying the standard design for NuScale Power’s small modular reactor in early 2023. This made NuScale the first company to clear the rigorous regulatory hurdles required to deploy an SMR in the United States. While the NRC has approved massive light-water reactors in the past, this was the first time a modular design received the green light.
Specifics of the NuScale Design
The certified design is markedly different from the gigawatt-scale reactors of the 20th century. Here are the concrete specifications that regulators approved:
- Output: Each individual power module is designed to generate 50 megawatts of electricity (MWe).
- Scalability: A power plant can house up to 12 of these modules, providing a total output of 600 megawatts. This allows utilities to scale up capacity as demand increases.
- Size: The reactors are physically small enough to be manufactured in a factory and shipped to the site by truck, rail, or barge. This reduces the complexity of on-site construction.
- Technology: It utilizes advanced light-water technology, which is a refined version of the conventional reactors currently operating in the US, but with distinct safety upgrades.
Why "Small" Matters: The SMR Advantage
The shift toward SMRs is not just about size. It is about rethinking how nuclear energy is integrated into the modern electrical grid. The approval validates several key technological shifts that differentiate SMRs from their predecessors.
Passive Safety Systems
One of the most critical aspects of the NuScale design is its passive safety system. In traditional reactors, active pumps are required to circulate water and keep the core cool. If power fails, backup generators must kick in to run those pumps.
The approved SMR design relies on physics rather than pumps. It uses natural convection, gravity, and the heat conduction of the water to cool the reactor. In the event of an emergency shutdown, the reactor can cool itself indefinitely without the need for operator intervention, AC or DC power, or additional water. This significantly reduces the risk of accidents similar to what happened at Fukushima.
Factory Fabrication vs. On-Site Construction
Traditional nuclear plants are plagued by cost overruns because they are essentially massive, custom infrastructure projects built outdoors. SMRs aim to solve this through factory fabrication.
- Quality Control: Building modules in a controlled factory environment reduces errors and improves consistency.
- Speed: Site preparation and reactor manufacturing can happen simultaneously, potentially cutting years off the deployment timeline.
- Cost Predictability: The goal is to turn nuclear reactors into a product rather than a project, driving down costs through economies of scale.
The Economic and Regulatory Reality
While the certification is a major victory, the path to deployment remains complex. The NRC approval proves the technology is safe, but the industry still faces economic hurdles.
Following the certification, NuScale had planned to build its first plant, the Carbon Free Power Project, in Idaho. However, that specific project was cancelled in late 2023 due to rising subscription costs for the power. Despite this economic setback, the regulatory certification remains valid. The design approval means that any utility company in the US can now reference this certified design when applying for a license to build and operate a nuclear power plant. They do not need to re-litigate the safety of the reactor core itself, which streamlines the licensing process significantly.
Future Outlook and Competitors
The approval of the NuScale design has set a precedent for other companies currently navigating the NRC pipeline. Several other developers are working on advanced designs that differ from NuScale’s light-water approach, including:
- TerraPower: Backed by Bill Gates, this company is developing the Natrium reactor, which uses liquid sodium for cooling instead of water. They are targeting a site in Wyoming.
- X-energy: This company is working on a high-temperature gas-cooled reactor using distinct “pebble bed” fuel.
The NRC is currently adapting its frameworks to review these non-light-water designs (Part 53 rulemaking), aiming to create a more agile regulatory environment that maintains safety without unnecessary red tape.
Frequently Asked Questions
What company received the first SMR approval?
NuScale Power Corporation, based in Portland, Oregon, received the first standard design certification from the US Nuclear Regulatory Commission (NRC).
How is an SMR different from a regular nuclear plant?
SMRs are much smaller (under 300 MWe per unit) and are designed to be built in factories and shipped to the site. They often feature “passive safety” systems that shut down and cool the reactor automatically without human intervention or backup power.
Is the approved reactor being built right now?
The specific design that was certified (50 MWe) is approved for use. However, NuScale is currently shifting focus to an uprated version of the design (77 MWe per module) which is currently under review. The first planned construction project in Idaho was cancelled in 2023, but the technology remains available for future projects.
Is the waste issue solved with SMRs?
SMRs still produce radioactive nuclear waste. However, because they are more efficient, the volume of waste per unit of electricity may differ. The waste is stored in robust dry casks on-site, similar to current large-scale plants, until a permanent national repository is established.
How safe are these new reactors?
The NRC certification indicates that the design meets the United States’ strict safety requirements. The passive safety features eliminate many failure points found in older reactors, specifically the reliance on electric pumps to prevent meltdowns.