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Nuclear Generator Movable By Cargo Plane. Not Only Possible, But Proven In the Early 1960s

Secretary of Energy Rick Perry muses about future nuclear generators.

Last week was National Clean Energy Week. On Tuesday, there was a wide ranging symposium with talks about nuclear energy, wind, solar, biomass, hydroelectricity, carbon capture and sequestration and natural gas.

Early in the day, Secretary of Energy Rick Perry and Secretary of the Interior Ryan Zinke participated in a panel discussion moderated by former New Hampshire Senator Kelly Ayotte. During that discussion, Sec. Perry spoke about the human tragedy that has been unfolding in the Caribbean since the islands were attacked by two major hurricanes in rapid succession. Naturally, he focused on the U.S. territories, but the same, or worse conditions exist in independent nations, British territories, and Dutch territories.

He spoke earnestly and with obvious emotion.

“I want to talk about an opportunity that we have right now. The Virgin Islands and Puerto Rico are devastated. Maybe one of the most tragic events in recent history with the hurricane that hit Puerto Rico. 3.5 million Americans who are without electricity. We’re trying to get micro generators down there. We’re trying to get fuel down there. Wouldn’t it make abundant good sense if we had small modular reactors that literally you could put in the back of a C-17 aircraft, transport to an area like Puerto Rico push it out the back end, crank it up, plug it in that could serve tens of thousands if not hundreds of thousands of people very quickly. That’s the type of innovation that’s going on in our national labs.”

That statement intrigued other participants enough that they brought it up at least twice in later panels.

For example, Charles Hernick of Citizens for Responsible Energy Solutions was the moderator of a panel discussion on innovation, research and development. He asked Marc Nichol, the senior project manager for the Nuclear Energy Institute’s program on new reactor deployment, small modular reactors and advanced reactors to help the audience understand how real that scenario might be.

Nichol responded by describing the fact that there were at least 20 different companies in various stages of developing new reactor designs, some of which are much smaller and more flexible than currently operating plants. He also described how some of them are specifically being designed for independent operation in small grids where the plant can be kept operating and ready to supply power as soon as off site power lines can be restored.

Skepticism From An Energy Pundit

Dr. Joe Romm, a Clinton Administration Department of Energy official, was dismissive of Perry’s description of future SMRs in a piece written for his Think Progress blog.

“Such small nuclear power plants are not expected to be commercialized until the mid-2020s, and even if they are, they are projected to be wildly expensive — just like current reactors — and not that small (650 tons). Nobody’s going to be “literally” putting one in a C-17 and pushing it out the back end on a small island ready to go. The U.S. territory doesn’t have time for such political pipe dreams.”

Dr. Romm has a different prescription for providing power to areas devastated by natural disasters.

“Microgrids built around cheap renewable power and battery storage are now the fastest and cheapest way to restore power — while at the same time building resilience into the grid against the next disaster.”

Who Is Right?

There are no air transportable nuclear plants available now. They are not expected to be available until sometime after the mid 2020s. Perry wasn’t suggesting that such systems were on the shelf.

Romm is also correct in noting that areas devastated by the one-two punch of Hurricanes Irma and Maria need power now. They cannot afford to wait two weeks, much less two months or ten years.

He is provably wrong, however, to describe Perry’s vision as a pipe dream and also to imply that there was no way anyone could literally put such a system onto an aircraft. It’s been done before. There’s video evidence from an era before computerized special effects that show actual hardware in the act of moving into and out of an airplane.

Army Produced Electricity With Air Transportable Nuclear Generator In September 1962

In the 1950s through the mid 1970s, the U.S. Army had a nuclear energy research and development program. That program, implemented at a time when there were many World War II veterans in decision making positions, was aimed at taking advantage of the incredible energy density of uranium fuel to solve a well understood logistical problem.

As noted in the above public information movie released by the Army in 1963, moving fuel represented 50% of the logistical effort of supporting a field army. At the time, about 1/8th of the fuel moved was dedicated to producing electricity.

One of the systems that the Army developed, the ML-1, was specifically aimed at providing a capable electricity generator that could be transported by air, rail, ship or truck. The designation, ML, stood for Mobile, Low Power Reactor. The ‘1’ meant it was the first of a kind.

Because of its evident potential for low weight compared to steam plants, the ML-1 used a closed Brayton Cycle compressor and turbine as the power off take system. It used nitrogen as the working fluid to transport heat from the reactor. The hot, pressurized nitrogen could spin a turbine, which was coupled to an electrical generator. After leaving the turbine, the nitrogen would be cooled and fed back into the compressor that pushed the gas through the reactor cooling channels.

The main part of the system fit on two skids, each weighing about 15 tons. One skid held the reactor, the other held the compressor, turbine, generator and heat exchanger. With a total weight of 30 tons, the two skids could be loaded onto a single truck. Cables and a control van would be carried on separate trucks.

With the state of material engineering and gas turbine machinery technology available in 1962, the ML-1 was expected to be able to produce 300 to 500 kilowatts of electricity. It’s fuel was expected to last at least two years before needing to be replaced. Set up time was measured in hours. Relocation after operation would have to wait a day or so while short lived fission products decayed.

ML-1 worked. It generated electricity for the first time in September 1962. However, it did not work very well because the designers had no experience in matching compressors to turbines for systems where the gas had to flow through nuclear reactors and exhaust through heat exchangers instead of directly into the atmosphere. Instead of the hoped for 300-500 kilowatts, the first of a kind (FOAK) unit produced a maximum of about 180 kilowatts.

After testing the system for a few hundred hours of operation, the designers were ready to make improvements.  Unfortunately, Army budgets in 1963 cut research and development funds to nearly zero in order to fund increased operations in Vietnam. In an era of “guns and butter” budgets, no one made room for nuclear energy research and development in the Army.

Regulations And Public Perceptions

As Secretary Perry noted, there are now regulations that would inhibit the development and operation of systems like the ML-1. As he also noted during his talk, many of those regulations have been imposed based on technological misunderstandings. Perry was not correct in blaming the public for those misunderstanding.

The public’s knowledge of nuclear energy and its potential is largely based on what the experts, the activists and the authorities have told them. Since the actual nuclear experts are cautious, speak very softly and mostly to each other, public knowledge has largely been shaped by more aggressive activists and by authorities who were moved by efforts of the vocal activists.

The compact nature of nuclear fuels is a matter of undeniable physics. So is the fact that nuclear fission does not produce any air or water pollution and the fact that hardened nuclear power plants have operated reliably in the most stressful environments available on earth and in space up to the limits of our solar system.

Though Romm cited a few examples of using solar power and batteries to supply small quantities of power in the aftermath of power outages following a hurricane, those systems cannot provide much electricity and they do not necessarily represent an improvement in resilience for withstanding future storms. That is especially true for “cheap” versions of the technology.

Here is a thought provoking photo of a large solar farm located near Charlotte Amalie on St. Thomas in the U.S. Virgin Islands following Hurricane Irma.

CHARLOTTE AMALIE, US VIRGIN ISLANDS – SEPTEMBER 17: Hurricane Irma destroyed almost all of the 16,748 panels in this solar farm September 17, 2017 in Charlotte Amalie, St Thomas, The U.S. Virgin Islands. Hurricane Irma slammed into the Leeward Islands on September 6 as a Category 5 storm, killing four and causing major damage on the islands of St. John and St. Thomas. (Photo by Chip Somodevilla/Getty Images,)

There are ways in which currently available nuclear energy systems can provide some comfort, safety and power for the devastated areas hammered by Hurricanes Irma and Maria – nuclear aircraft carriers have a long history of exceptional response in humanitarian crises. Not as well known, but reasonably well demonstrated is the fact that nuclear submarines have some capacity to supply electricity to islands.

The U.S. should do everything it can to assist and provide power now, but we should also diligently pursue responsible commercialization of the small nuclear power systems that were initially developed and proven possible by past generations.

Note: A version of the above was first published on It is republished here with permission.

The post Nuclear Generator Movable By Cargo Plane. Not Only Possible, But Proven In Early 1960s appeared first on Atomic Insights.

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John Miller's picture
John Miller on October 5, 2017

Rod, you provide some very reasonable and educational information on the facts about small nuclear power electricity generators. Also, what is rarely referred to by those who generally oppose nuclear power technologies is the fact that numerous nuclear power reactor-generators have been critical to enabling many space-orbital missions over the years. For example, refer to the website’s article: The History of Nuclear Power in Space. Yes, this technology is not necessary cheap, but the feasible power supply quantity is far greater than all current green energy emergency power supply options.