Matthew L. Wald via The Breakthrough Journal <thebreakthroughjournal+matthew-l-wald@substack.com>
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How Not To Innovate
Turning Opportunity into a Dead End
By Matthew L. Wald
January 3, 2025
Fort St. Vrain Nuclear Plant near Platteville, Colorado
In hindsight, the Fort St. Vrain reactor was a high-tech tragedy. Nobody was killed or injured, no company went out of business, and there were no mass layoffs, but there was a squandered opportunity that we are paying for decades later. And as we bring new kinds of advanced reactors into the world, we should be careful not to repeat the errors of that episode.
Ceran St. Vrain was a 19th-century American fur trapper of French descent. He was not a saint; that was just his surname. But perhaps he should be named the patron saint of giving up too soon.
The nuclear project named after him, located in the Colorado town of the same name about 40 miles north of Denver, looked good on paper. It produced steam at 1,000 degrees F, hotter than water-based reactors, which gave it the potential to substitute for coal in industrial applications. It took non-fissile thorium and turned it into fissile U233, essentially making some of its own fuel.
Its reactor vessel was made of concrete, which was potentially easier to fabricate than the kind used by water-based reactors, which is carbon steel with stainless steel cladding. It operated at lower pressure but higher temperature than a water-based reactor, a desirable combination.
Some glitches turned up during construction but nothing the builders couldn’t correct. And when fuel was loaded, neutron generation was almost exactly as predicted; no small feat in a first-of-a-kind reactor.
It looked like it had strong safety advantages. If it scrammed from 100 percent power, and all coolant circulation was lost after half an hour the temperature was still 500 degrees below the threshold for damage.
The project had top-notch participants; research by the Atomic Energy Commission’s Power Reactor Demonstration Program, Sargent & Lundy as the architect/engineering firm, and EBASCO as the general contractor.
But when it opened, it didn’t run very well. It had pumps to circulate the coolant material, helium, and the pumps had bearings that were lubricated with water. But the water leaked into the system even before the test program was complete. It spread through the reactor, and once inside, it corroded some parts. Helium often leaked too.
Power plant performance is measured with a metric called capacity factor. Compare actual energy production to what production would have been if it ran at 100 percent, 24/7/365. In the early days of pressurized water reactors, the only type of power reactor now operating in the United States, capacity factors were commonly in the 60 percent range, and after decades of operating experience, they now average over 90 percent, but St. Vrain was 14 percent.
Its owners were struggling through a period of economic slowdown— caused, ironically by high prices for another source of energy, oil—and electricity demand had slacked off. Natural gas was available and easy to understand. And the reactor was regulated under the system then common, with ratepayers reimbursing the company for the investment, and state officials were pressuring the owner, Public Service Company of Colorado, to give up.
So, after 18 months they pulled the plug on St. Vrain.
Hindsight
That was in 1988. Fast forward to 2020, and the government, eager to 3
revive the gas-graphite combination, promised a company in Washington, D.C., X-energy, that it would invest more than $1.2 billion to rush the first model into production, under the Advanced Reactor Demonstration Program. Few utilities have much appetite for a first-of-a-kind generator, but Dow stepped up to agree to buy four of them for a chemical plant in Texas that now relies on natural gas to make process steam.
At a time of growing energy demand and growing urgency to develop carbon-free sources, it is obvious that we would have been better off to nurture a project in the 1980s until it reached commercial competitiveness even if the first model had design flaws that made it an industrial lemon. The problem with first-of-a-kind projects is that the costs and the benefits don’t fall on the same people. So, the electricity consumers of Colorado were spared an expense, and we dropped the technology.
Now, we face a different tragedy: for the first time in a generation, there is strong demand for new nuclear power, and the industry has no proven, mature advanced reactor ready to go. There is a cliché today that businesses should learn to “fail fast,” but that makes sense only if you draw the correct lesson from the failure, which in this case was to try again with a better helium circulator, and not to fall back on triedand-true technology that would eventually become obviously troublesome, like fossil fuels.
St. Vrain isn’t the only example of a technology that was deployed early and died too soon. Fermi 1, south of Detroit, followed a similar trajectory.
Fermi-1 was a sodium-cooled fast reactor, a design that gives off highenergy neutrons. Add a blanket of uranium-238, the abundant form of Uranium, and it becomes a “breeder,” a machine that makes more fuel
than it consumes, because the U-238 will capture a neutron and be turned into plutonium-239, an excellent reactor fuel. Capture is more likely when the neutrons are moving fast.
Sodium coolant was integral to the design because it was unlikely to interact with the neutrons, unlike water in other reactor types, which slows the neutrons down. Sodium is in many ways superior to water, because it does not want to expand as much when heated; thus, it can be used in a low-pressure reactor.
The plant was a commercial-scale follow-up to EBR-1, an experimental reactor in Idaho.
Like St. Vrain, which came a few years later, Fermi-1 also had operating troubles. The flow of the sodium coolant was interrupted by a blockage, and some of the fuel melted. The reactor shut down and there was no release of radiation beyond the containment building.The damage was repaired and the reactor re-started, although that took four years.
Detroit Edison ran it for another two years, and then shut it down. Its younger siblings, Fermi-2 and -3 are conventional light water reactors.
At both the Fort St. Vrain and Fermi-1, the issues were not so much reactor physics as they were materials science. Today, water does not degrade components very much in reactors, but only because the operators have learned from painstaking experience that tight control of water chemistry is essential. Moving to a different coolant poses new problems. Helium molecules, for example, are very small, so seals are tricky. Sodium poses a different set of problems.
And new problems are likely to turn up in new designs for advance
reactors, now moving towards deployment. These will be unforeseen problems with equipment, the kinds of issues that it took years for current-generation reactors to work out. Or there could be difficulties with interactions between materials used in advanced reactors, materials more complicated than the plain old water we use in current designs.
Some of these problems could cause shutdowns that will last for a while, while engineers analyze what went wrong, redesign parts, and fabricate new ones.
Making Better Use of Failure
We could face problems that we haven’t seen before because the industry and the government missed the opportunity to discover the issues last time. They did not extract the maximum value from either St. Vrain, the gas-graphite design, or from Fermi-1, the sodium design, And now TerraPower is building a sodium fast reactor, under the same program that X-energy is using for its gas-graphite reactor.
Natrium has advantages over the builders of Fermi-1, including decades of engineering advances, but again, a reactor for which there is a market now will not be deployed for at least the next several years. Meeting our energy and climate challenges would have been easier if Fermi-1, although uneconomic, had been nurtured for a while longer.
The Dow and TerraPower projects might be better situated than Fort St. Vrain and Fermi were. Dow has deep pockets and doesn’t have a public service commission to criticize it; it wants the reactor so it can market its products as climate friendly and may have more patience than utility. TerraPower wants a product that will “scale,” a working model it can point to so it can sell a few dozen more.
The early problems will give people who never liked nuclear energy an “I-told-you-so” moment. But their verdict, right or wrong, will be premature if it comes when the reactors first start running.
Both companies might do well to follow the pattern of companies that build cars or airplanes; they may expect to lose money on the first few and make it up as the bugs get worked out and their commercial viability becomes clear. This may be essential when the first project is a full-scale model. Another advanced reactor company, Kairos Power, is taking an entirely different approach, iterating with model after model, demonstrating component after component, before moving to a full-scale machine. But this is atypical for reactor development.
It may also be time for the government to learn a lesson: if you invest in something as complicated as a first-of-a-kind reactor, the endpoint isn’t when construction is finished, fuel is loaded, and operators achieve the first criticality. It’s when the model becomes a commercial success.