Manufacturing Small Nuclear Reactors - What would they mean for Wyoming?

by Wyoming Liberty Group

As we in Wyoming have heard a lot lately, some political and economic interests are touting the idea of making our state an above-ground dry cask repository location for commercial spent nuclear fuel rods, which is a fancy way of referring to nuclear waste that needs to be put somewhere for storage for decades. The 2025 bill, HB16 – Used nuclear fuel storage - amendments, failed in committee, but we will likely see the topic return as an interim issue and make another run in 2026. Proponents tout the idea by saying that it will generate millions, if not billions, in much-needed revenue and that it will also create new jobs and industries.

The same folks in favor of pursuing nuclear waste storage in Wyoming also hail the newer designs of nuclear power plants called advanced nuclear reactors. What are these newfangled things? Well, in simple terms, this broad category includes next-generation reactor designs with improved efficiency, safety, and waste management compared to traditional nuclear reactors. The Natrium reactor, currently underway in Kemmerer, WY, falls into this category because it uses a sodium-cooled fast reactor (SFR) design with an integrated molten salt energy storage system, which allows it to ramp up power production as needed. For more information on the waste associated with this design, please take a few moments to watch our recent interview with Dr. Gordon Edwards.

Proponents also are eager to pursue bringing a small modular reactor manufacturing industry to Wyoming. Small modular reactors, or SMRs, typically produce 300 megawatts or less and are designed to be factory-built and modular, meaning components can be assembled on-site. Most SMRs use conventional light-water reactor technology but on a smaller scale. One of the companies interested in manufacturing in Wyoming, which was mentioned during the committee discussion over HB16 and SF186, aims to build microreactors that are a sub-category of SMRs and produce 1 megawatt. The design is intended to replace diesel generators. Other potential companies could include SMRs that produce around 50-300 megawatts.

Why? Proponents cite several benefits of SMRs, such as cost savings; they're less expensive to construct than traditional, bigger nuclear power plants. These smaller designs also take up less space, and advocates say they are safer than the bigger nuclear plants. Moreover, they claim that SMRs are more reliable in producing electricity continuously when needed.

All of which sounds great, doesn't it?

But —and there's a but—let's leave aside all of these claims and address one significant feature that is often ignored in all of the fanfare. Small modular reactors, the so-called present and future of the nuclear power industry, often produce even more nuclear waste than traditional reactors.

That's according to researchers who published their findings in the Proceedings of the National Academy of Sciences, or PNAS, a peer-reviewed journal of the National Academy of Sciences. PNAS is described as "one of the world's most-cited and comprehensive multidisciplinary scientific journals, publishing more than 3,500 research papers annually." For what it's worth, the publication also "serves as an authoritative source of high-impact, original research that spans the biological, physical, and social sciences, with global reach and open submission to researchers worldwide."

In other words, the published research on small modular reactors isn't just idle talk.

This is what the researchers said, in part: "Small modular reactors (SMRs), proposed as the future of nuclear energy, have purported cost and safety advantages over existing gigawatt-scale light water reactors (LWRs). However, few studies have assessed the implications of SMRs for the back end of the nuclear fuel cycle. The low-, intermediate-, and high-level waste stream characterization presented here reveals that SMRs will produce more voluminous and chemically/physically reactive waste than LWRs, which will impact options for the management and disposal of this waste."

That's a lot of complicated scientific language. But it distills to this: While smaller nuclear reactors are in vogue these days, little attention has been paid to the volume and level of radioactivity in the nuclear waste they produce. This study indicates that these smaller modular reactors can make far more and vary by design.

To be fair, it should be noted that the researchers examined three specific kinds of smaller modular reactors, including water, molten salt, and sodium-cooled SMRs. While there could be other forms of smaller modular reactors, those three are among the most common, and the researchers concluded that such "designs will increase the volume of nuclear waste in need of management and disposal by factors of 2 to 30."

Which is no small matter.

In addition, the study indicated that there are some inherent issues regarding the waste produced by smaller nuclear reactors: "Since waste stream properties are influenced by neutron leakage, a basic physical process that is enhanced in small reactor cores, SMRs will exacerbate the challenges of nuclear waste management and disposal," the researchers stated.

As such, it is important that we understand all of the ramifications, including some factors that may be overlooked, when assessing the idea of making Wyoming a home for spent nuclear fuel from commercial sources and SMR manufacturing.

Or, as the researchers of this study said, "Although the costs and timeline for SMR deployment are discussed in many reports, the impact that these fuel cycles will have on nuclear waste management and disposal is generally neglected."

To view the full PNAS research article "Nuclear waste from small modular reactors" Click Here