In case you have not yet seen this open letter to Bill Gates, here it is:
We need all the resources we can get to counter the coordinated campaign to convince the public and Congress that nuclear is “clean” and an answer to the climate crisis. Arnie has the credentials to make the case.


Jane Swanson

An Open Letter to Bill Gates About his Wyoming Atomic Reactor

An Open Letter To Bill Gates About His Wyoming Atomic Reactor

Dear Mr. Gates,

I am writing this open letter to you because I believe you have crossed the line by leveraging your fortune to maneuver State Governments and, indeed, the U.S. Government to siphon precious taxpayer funds supporting your latest atomic contrivance in Wyoming. Of course, how you spend your personal fortune is your decision and yours alone. Still, I question your zeal to leverage that fortune by securing additional public funds for an unproductive techno-solution that claims to solve the climate crisis! Your latest technofix is the scheme to have taxpayers fund your new nuclear power concept in Wyoming, claiming that it will mitigate the climate crisis. It won’t!

Atomic power generation is not part of your skillset, but it is mine. The many facets of nuclear energy have been areas of my professional focus for the last 50 years. Beginning in 1971 with two nuclear engineering degrees, a Reactor Operator’s license, a corporate Senior Vice President position for an atomic licensee, a nuclear safety patent, two peer-reviewed papers on radiation, as well as a best-selling book on Fukushima, nuclear power is in my wheelhouse, not yours.

Based on my experience, I am writing this public letter to express my fear that you have made an enormous mistake by proposing to build a sodium-cooled Small Modular Reactor (SMR) in Wyoming. Mr. Gates, your atomic power company Natrium (the Latin word for sodium), is following in the footsteps of a seventy-year-long record of sodium-cooled nuclear technological failures. Your plan to recycle those failures and resurrect liquid sodium again will siphon valuable public funds and research from inexpensive and proven renewable energy alternatives. Moreover, spending public funds on Natrium will make the global climate crisis worse, not better!

Let me explain why Natrium is doomed. As you probably have already been told, all present-day atomic reactors are water-cooled Light Water Reactors (LWRs). Similarly, all U.S. coal, oil, and gas-fired electric plants heat water, not exotic coolants. While some Small Modular Reactor (SMR) concepts retain water cooling, Natrium’s proposed design deviates from this pattern by using a strange and unsuccessful coolant and specially designed steam generators to cool the atomic chain reaction and remove the atomic heat. Nuclear power concepts that do not use water for cooling are called Non-Light Water Reactors (or NLWRs). Natrium claims that cooling with liquid sodium is allegedly safer and more reliable than traditional water-cooled reactors. What evidence exists to support your assertion?

World-renowned energy economist Mycle Schneider calls Natrium and the other proposed conceptual reactors “PowerPoint Reactors” as none are close to being fully designed. Yet, Natrium and other potential vendors market these reactors as if the successful and safe operation were a fait accompli. According to Mycle Schneider, as reported in Politico E.U.:

“All they have right now are basically PowerPoint reactors — it looks nice on the slide but they’re far from an operating pilot plant. We are more than a decade away from anything on the ground.”

The Union of Concerned Scientists (UCS) recently completed an exhaustive, 140-page study of the supposed safety improvements claimed by NLWR (SMR) manufacturers like Natrium. Entitled Advanced Isn’t Always BetterUCS concludes:

“But a fundamental question remains: Is different actually better? The short answer is no. Nearly all of the NLWRs currently on the drawing board fail to provide significant enough improvements over LWRs to justify their considerable risks.”

Recently, the media and governors in western states have become enthralled with one NLWR/SMR design hyped by you and your well-funded publicity team at Natrium. Using your successes at Microsoft, you are now asking state and national governments to bankroll a “fast reactor” concept cooled by liquid sodium.

According to Forbes Magazine:

“Wyoming To Lead The Coal-To-Nuclear Transition

Interest for new nuclear plants is growing beyond Wyoming as states in the western region like Montana, Nebraska, Utah, Idaho and North Dakota reevaluate the role of nuclear energy – particularly applications for advanced nuclear reactors …the brainchild of Bill Gates, …has developed a 345 MW sodium-cooled fast reactor with a molten salt-based energy storage system.”

The history of a sodium-based atomic coolant does not support your grandiose claims of success. Mr. Gates, the marketing hype associated with your latest “brainchild” ignores more than 70-years of failures using liquid-sodium-based atomic reactor coolant. Let me detail just a few of the monumental failures created by attempting to develop liquid-sodium reactors. Unfortunately, I do not believe you have adequately studied any of these alarming failures before pressing for government funds to pursue your idea.

According to Scientific American, liquid sodium “is no mere novelty; as dangerous as it is captivating…  Sodium has significant disadvantages. On contact with air, it burns; plunged into water, it explodes.”

The Bulletin of the Atomic Scientists goes even further, stating:

Unfortunately, this pitch glossed over stubborn facts… because plutonium fast-breeder reactors use liquid metal coolants, such as liquid sodium, operating them safely is far more challenging and expensive than conventional reactors. When private industry tried in the early 1960s to operate its own commercial-sized fast-breeder, Fermi I, the benefits were negative. Barely three years after Fermi 1 came online, a partial fuel meltdown in 1966 brought it down… These facts, however, are rarely emphasized….”

In addition to the meltdown at Fermi 1, highlighted in the book We Almost Lost Detroit, other sodium-cooled reactors have failed in the United States and worldwide. Beginning in 1950, the Navy attempted to develop a sodium-cooled reactor for the Seawolf submarine. According to the American Nuclear Society, Admiral Rickover, the founder of the nuclear Navy, testified to Congress in 1957 stating:

“We went to full power on the Seawolf alongside the dock on August 20 of last year.  Shortly thereafter, she developed a small leak. It took us 3 months, working 24 hours a day, to locate and correct the leak. This is one of the serious difficulties in sodium plants.”

Rickover killed the Navy’s sodium-powered reactor due to its leaks, volatility, sodium-reactor repairs take too long, and radiation exposure to workers was too high. The problem of high radiation exposures to maintenance personnel while repairing inevitable sodium leaks was also highlighted by Rickover in that same 1957 testimony when he stated:

“Sodium becomes 30,000 times as radioactive as water. Furthermore, sodium has a half-life of 14.7 hours, while water has a half-life of about 8 seconds.”

Making rapid repairs in a sodium-cooled reactor is impossible because the sodium becomes highly radioactive as it flows through the reactor core. In addition, it stays radioactive for weeks after shutdown. In contrast, water used to cool conventional reactors is highly radioactive for about one minute.

After failed attempts to use liquid sodium on the Seawolf and Fermi 1, nuclear zealots convinced the U.S. Congress to subsidize another sodium-cooled reactor at Clinch River in Tennessee. The concept of a sodium-cooled reactor at Clinch River originated well before the meltdown at Fermi 1, yet, Clinch River continued receiving extensive government subsidies until 1984. Therefore, overcoming the safety issues presented by cooling atoms with liquid sodium led to delays and cost overruns that were significant factors when Congress finally killed the project. However, severe, game-changing safety concerns were also a factor in the cancelation of the project. According to The Rise and Demise of the Clinch River Breeder Reactor in Scientific American:

“In 1982 … the Energy Department videotaped safety tests it had conducted of how molten sodium might react once it came in contact with the reactor’s concrete containment structure. Concrete contains water crystals. Molten sodium reacts explosively when it comes in contact with oxygen, including oxygen contained in water. What the test demonstrated and the video showed was concrete exploding when it came in contact with liquid sodium.”

Even after the cancelation of the Clinch River fiasco, those same nuclear zealots continued to pursue the fantasy of a sodium-cooled fast breeder reactor at the Monju site in Fukui Prefecture, Japan. As a result, construction of the Monju liquid sodium reactor began in 1985, with the sodium-cooled reactor finally operational 10-years later. It did not operate long. However, after running for only 4-months, plagued by the inevitable sodium leak and sodium fire, the Monju reactor had an emergency shutdown!

According to a report issued by the Monju Construction Office entitled Sodium Leak at Monju-Causes and Consequences, Monju’s designers did not anticipate the failure mode that caused the leak.

“On December 8, 1995, a sodium leak from the Secondary Heat Transport System (SHTS) occurred in a piping room of the reactor auxiliary building at Monju. The sodium leaked through a thermocouple temperature sensor due to the breakage of the well tube of the sensor installed near the outlet of the Intermediate Heat Exchanger (IHX) in SHTS Loop C… On the basis of the investigations, it was concluded that the breakage of the thermocouple well was caused by high cycle fatigue due to flow induced vibration in the direction of sodium flow.”

After ten years of construction, Monju had four months of operation, followed by a fifteen-year shutdown. Monju was restarted in 2010 and operated for less than one year when the equipment used for refueling fell into the reactor while refueling was in progress. It never restarted. The simple fact is that the Monju sodium reactor took ten years to construct, ran intermittently for one year, and failed to operate for twenty years. And then, there is the matter of Japan’s government-subsidized costs, which ultimately exceeded $11 Billion. As Reuters noted:

“The move to shut the Monju prototype fast breeder reactor in Fukui prefecture west of Tokyo adds to a list of failed attempts around the world to make the technology commercially viable and potentially cut stockpiles of dangerous nuclear waste…. With Monju’s shutdown, Japan’s taxpayers are now left with an estimated bill of at least 375 billion yen ($3.2 billion) to decommission its reactor, on top of the 1 trillion yen ($8.5 billion) spent on the project.”

A half a world away from Japan, France generates 75% of its electricity from light water-cooled atomic reactors. France also considered sodium reactors. However, given the repeated failures of sodium-cooled technology in Japan and the U.S., and with the falling price of renewable power, in 2019, France chose not to pursue the path you and Natrium are trying to follow. According to Reuters, France has decided to cancel its sodium-cooled reactor designs for at least half a century!

“PARIS (Reuters) – France’s CEA nuclear agency has dropped plans to build a prototype sodium-cooled nuclear reactor, it said on Friday, after decades of research and hundreds of millions of euros in development costs. Confirming a report in daily newspaper Le Monde, the state agency said it …is no longer planning to build a prototype in the short or medium term. “In the current energy market situation, the perspective of industrial development of fourth-generation reactors is not planned before the second half of this century.”

I could excerpt many more sodium-cooled reactor debacles, but I think I have made my point! History shows a legacy of failures in the pursuit of the sodium reactor fantasy. As Admiral Rickover said almost 70 years ago, sodium reactors are “expensive to build, complex to operate, susceptible to prolonged shutdown as a result of even minor malfunctions, and difficult and time-consuming to repair.”

Mr. Gates, it’s time to face the music (and the facts) – your supposedly foolproof, sodium-cooled Natrium brainchild will encounter those same obstacles.

During my fifty years of developing nuclear power expertise, I have learned that sooner or later, in any foolproof system, the fools are going to exceed the proofs. So now is the time to stop the Natrium marketing hype and free up those precious public funds to pursue low-cost and dependable renewable energy during the time frame necessary to help prevent catastrophic climate crises!


Arnold “Arnie” Gundersen, Chief Engineer, Fairewinds Energy Education

Arnie Gundersen is the Chief Engineer, board member, and resident “science guy” at the Fairewinds Energy Education NGO. Since the catastrophe at Fukushima, Arnie focuses his energy worldwide on the migration of radioactive microparticles. During his multiple trips to Japan, Arnie has met and trained community-volunteer citizen-scientists to study the migration of radioactive microparticles from Fukushima in two co-authored peer-reviewed scientific articles.