When you think of innovative advancements in nuclear power technology, places like the Idaho National Laboratory and the Massachusetts Institute of Technology probably come to mind. But today, some very exciting nuclear power development work is being done in West Texas, specifically, at Abilene Christian University (ACU). That’s where Natura Resources is working to construct a molten salt–cooled, liquid-fueled reactor (MSR).
“We are in the process of building, most likely, the country’s first advanced nuclear reactor,” Doug Robison, founder and CEO of Natura Resources, said as a guest on The POWER Podcast.
Natura has taken an iterative, milestone-based approach to advanced reactor development and deployment, focused on efficiency and performance. This started in 2020 when the company brought together ACU’s NEXT Lab with Texas A&M University; the University of Texas, Austin; and the Georgia Institute of Technology to form the Natura Resources Research Alliance. In only four years, Natura and its partners developed a unique nuclear power system and successfully licensed the design. The U.S. Nuclear Regulatory Commission (NRC) issued a construction permit for deployment of the system at ACU last September.
Called the MSR-1, ACU’s unit will be a 1-MWth molten salt research reactor (MSRR). It is expected to provide valuable operational data to support Natura’s 100-MWe systems. It will also serve as a “world-class research tool” to train advanced reactor operators and educate students, the company said.
Advantages of MSR Technology
The technology is not new. It was actually proven decades ago. “A molten salt reactor was built at Oak Ridge in the 1960s—the Molten Salt Reactor Experiment or the MSRE—and that reactor functioned for about five years, then was shelved in favor of solid-fuel or light-water reactors [LWRs] that we’re all familiar with,” Robison explained. “That was really a decision made because the customer in the 1960s was the Department of Defense, and Admiral Rickover was building a nuclear Navy, and they needed to enrich uranium to plutonium for warheads, and solid fuel reactors are more suited for those purposes,” Robison added.
The coolant is one of the main differences between LWRs and MSRs. As the names imply, an LWR is cooled by water, while an MSR is cooled by molten salt.
LWRs require thick pressure vessels and high-pressure piping to safely contain pressurized water, provide radiation shielding, and ensure long-term structural integrity. Today, there are no U.S. manufacturers with the capability to forge a large nuclear reactor vessel, so they must be sourced overseas.
Notably, molten salt turns from a solid to a liquid at about 450C, but it doesn’t turn to a gas until about 1,400C, which is above the melting point of stainless steel. “What that means is you can never get to the point to where the salt flashes to a steam, so we operate at very, very high temperatures, which is a big advantage because the high process heat—from an efficiency standpoint and manufacturing standpoint—is incredibly valuable, but we operate at atmospheric pressure, because the salt never transfers into a gas. It goes from a solid to a liquid. And, if you were to have some kind of leak or release, once you drop below 450 degrees C, it immediately freezes back into a solid, so kind of picture candle wax, if you will. So, it’s called ‘walk-away safe’ for that reason. You don’t need a containment dome,” explained Robison.
These factors significantly reduce the cost of MSR facilities compared to LWR plants. MSR reactor vessels, for example, can be manufactured by Teledyne Brown Engineering in Huntsville, Alabama, and perhaps elsewhere in the U.S. Robison said everything needed to construct an MSR can be made in America, and he expects much of it to be manufactured in Texas. “Governor Abbott has said, ‘We want Texas to capture this industry,’ ” noted Robison. “Houston, Texas refers to itself as the energy capital of the world. So, we’ve been working with the Greater Houston Partnership and the Houston Energy Transition Initiative [to answer the question] ‘How does that manufacturing happen not just in the U.S., but how does it happen in Texas?’ ”
Liquid fuel also provides an advantage for MSRs versus the LWR’s solid-fuel design. “[In] the solid-fueled reactor, you have the fuel inside the fuel rod. And under current technology, when you burn 3% to 5% of the fuel, then at that point, the rod begins to decay. That is your first level of containment, so you have to pull the rod. That now becomes ‘spent nuclear fuel’ and enters into the waste stream. You still have 95% to 97% of perfectly good fuel inside that fuel rod. And now the problem becomes: ‘What do we do with this nuclear waste that’s going to be around for 100,000 years?’ ”
In an MSR, the fuel is dissolved in the salt. “What that means is we burn practically 100% of the fuel. We do not throw unspent nuclear fuel away, and so our efficiency goes way up. We do not generate the waste that you see with a light-water reactor,” said Robison. “In fact, molten salt reactors can utilize current stockpiles of spent nuclear fuel that is sitting in storage at different nuclear reactors around the nation, and we can take that fuel, and re-utilize that as fuel for a molten salt reactor.”
Commercial Projects Announced
Natura is not only focused on its ACU project, but it is also moving forward on commercial reactor projects. In February, the company announced the deployment of two advanced nuclear projects, which are also in Texas. These deployments, located in the Permian Basin and at Texas A&M University’s RELLIS Campus, represent significant strides in addressing energy and water needs in the state.
“Our first was a deployment of a Natura commercial reactor in the Permian Basin, which is where I spent my career. We’re partnering with a Texas produced-water consortium that was created by the legislature in 2021,” said Robison.
“Produced water” is the water brought to the surface during oil and gas extraction processes. It is a byproduct of hydrocarbon production and typically consists of formation water that was originally present in the underground reservoir, along with additional water introduced during extraction operations. It typically has a salinity that is three times that of seawater, but it can be double or triple that in some instances. In any case, it cannot be released on the surface and must currently be reinjected back into the formation, which can create additional problems.
One of the things that can be done with the high process heat from an MSR is desalinization. “So, we’re going to be desalinating produced water and providing power—clean power—to the oil and gas industry for their operations in the Permian Basin,” said Robison.
Meanwhile, at Texas A&M’s RELLIS Campus, which is located about eight miles northwest of the university’s main campus in College Station, Texas, a Natura MSR-100 reactor will be deployed. The initiative is part of a broader project known as “The Energy Proving Ground,” which involves multiple nuclear reactor companies. The project aims to bring commercial-ready small modular reactors (SMRs) to the site, providing a reliable source of clean energy for the Electric Reliability Council of Texas (ERCOT).
Robison believes the Stargate Project, a massive $500 billion initiative aimed at building advanced hyperscale data centers across the U.S. to power next-generation artificial intelligence (AI) models, could also present an opportunity for Natura. “The very first deployment of Stargate is scheduled to be in Abilene, Texas. We can actually see the data center that’s being constructed from the windows of our offices,” he said. “We may see something happen there just given the proximity of what they’re doing and what we’re doing,” Robison envisaged.
To hear the full interview with Robison, which contains more about the creation of Natura Resources, the selection of MSR technology for its design, its collaboration with ACU, the work done to license the reactor, and much more, listen to The POWER Podcast. Click on the SoundCloud player below to listen in your browser now or use the following links to reach the show page on your favorite podcast platform:
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—Aaron Larson is POWER’s executive editor (@AaronL_Power, @POWERmagazine).