Powering the Future

Why NASA wants to put a nuclear power plant on the moon

Key Points
  • NASA and the U.S. Department of Energy will seek proposals from industry to build nuclear power plants on the moon and Mars to support its long-term exploration plans.
  • The goal is to have a flight system, lander and reactor ready to launch by 2026.
  • The facility will be fully manufactured and assembled on Earth, and tested for safety.
  • The nuclear power plants will provide enough electrical power to establish an outpost on the moon or Mars.
Illustration of a nuclear fission power system concept on the Moon.
NASA

NASA and the U.S. Department of Energy will seek proposals from industry to build a nuclear power plant on the moon and Mars to support its long-term exploration plans. The proposal is for a fission surface power system, and the goal is to have a flight system, lander and reactor ready to launch by 2026.

Anthony Calomino, NASA's nuclear technology portfolio lead within the Space Technology Mission Directorate, said that the plan is to develop a 10-kilowatt class fission surface power system for demonstration on the moon by the late 2020s. The facility will be fully manufactured and assembled on Earth, then tested for safety and to make sure it operates correctly.

Afterwards, it will be integrated with a lunar lander, and a launch vehicle will transport it to an orbit around the moon. A lander will lower it to the surface, and once it arrives, it will be ready for operation with no additional assembly or construction required. The demonstration is expected to last for one year, and could ultimately lead to extended missions on the moon, Mars, and beyond.

"Once the technology is proven through the demonstration, future systems could be scaled up or multiple units could be used together for long-duration missions to the moon and eventually Mars," Calomino said. "Four units, providing 10 kilowatts of electrical power each, would provide enough power to establish an outpost on the moon or Mars. The ability to produce large amounts of electrical power on planetary surfaces using a fission surface power system would enable large-scale exploration, establishment of human outposts, and utilization of in situ resources, while allowing for the possibility of commercialization."

NASA is working on this with the Idaho National Laboratory (INL), a nuclear research facility that's part of the DOE's complex of labs. But is the plan realistic, and is delivery possible six years from now? According to Steve Johnson, director of the Space Nuclear Power and Isotope Technologies Division at the Idaho National Laboratory, the answer is "yes."

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"We are able to leverage years of research and development work on advanced fuels and materials as well as recent commercial space transportation advances to reduce risk to the schedule, to meet the 2026 date," Johnson said. "We really are striving to bring the commercial nuclear industry innovation to the table to work with NASA and the aerospace industry utilizing existing technologies."

Calomino said that the technologies that are critical to the success of this project are a nuclear reactor, power conversion, heat rejection and space flight technology.

How the nuclear plant will work

"A low enriched form of nuclear fuel will power the nuclear core," he said. "The small nuclear reactor will generate heat that is transferred to the power conversion system. The power conversion system will consist of engines that are designed to operate on reactor heat rather than combustible fuel. Those engines use the heat, convert it to electric power that is conditioned and distributed to user equipment on the lunar and Martian surfaces. Heat rejection technology is also important to maintain the correct operating temperatures for the equipment."

Johnson said that in addition to the research and development that has taken place over the past several decades, the existing physical infrastructure dedicated to creating the nuclear reactor, power conversion, heat rejection and space flight technology will make the 2026 timeline attainable.

"We can utilize existing facilities and technical expertise resident at our national laboratories to support this important initiative to meet the country's timeline," he said. "At INL, we are supporting a future industry/partnership effort in the coming months to design this demonstration reactor, bringing together aerospace, nuclear and power companies for this monumental effort."

A photo of the moon taken by SpaceIL's Beresheet spacecraft in orbit.
SpaceIL

Calomino said that the agency has partnered with the DOE, and they will jointly define mission and system requirements. The INL will manage development contracts for the fission surface power lunar system, including its reactor and shield, power conversion system, heat rejection system, and power management and distribution system.

"The fission surface power system will be designed to operate at around 10 kilowatts of electrical power for around 10 years," he said, adding that 10 kilowatts is roughly equivalent to the amount of energy needed to power five to eight large households. 

Calomino said that the laboratory issued a request for information to gauge industry interest and solicit designs for the project. It received 22 written responses from large and small companies, all from the aerospace, nuclear, and power conversion sectors.

While he didn't give the names of any of these companies, he would say that the companies were all experienced in making nuclear reactors, developing spaceflight technology, and manufacturing the specialized equipment that will be needed for this particular project. He added that NASA and the DOE plan to release another request for proposals, related specifically to nuclear fission power, in early 2021. Future contract award values are still to be determined.

"The government plans to award multiple short-term contracts to develop a preliminary design, then a subsequent large contract for the final flight hardware development," he said. "The project anticipates that companies will form teams to address all technology areas required to develop this unique and complex power system."

Calomino said that the project is so complex because it requires the integration of different organizational engineering skill sets.

"Companies that specialize in nuclear reactor development may not have corporate knowledge or experience developing spaceflight equipment or power conversion systems," he said. "Additionally, there may be other specialized communications equipment, sensors, power conversion technology, and heat transfer technology that is obtained most efficiently by forming partnerships."

Is a nuclear reactor safe on the moon?

The idea of a nuclear reactor on the moon may seem unusual to the general public — or even dangerous. Andrew Crabtree, founder of the Get Into Nuclear employment agency, said that while there were many factors to consider in this effort, the issue of whether it's safe to use nuclear power in space is not one of them.

"Nuclear energy has been used in space numerous times before," Crabtree said. "Atomic energy has been operating on the moon since the flight in November 1969 of Apollo 12 successfully withstanding immense temperature variations. Apollo 12 marked the first use of a nuclear electrical power system on the moon."

He also said that people with concerns about keeping space free of pollution should rest easy.

"Before you say something like, 'We shouldn't be polluting space with nuclear waste,' know that almost every single space mission you've ever heard of has used radioisotope thermoelectric generators, which have Plutonium-238 as their electricity source."

Shel Horowitz, a profitability and marketing consultant for green businesses said that putting a nuclear power plant on the moon would be a boondoggle and a wholly unnecessary one at that.

"With the rapidly falling cost of truly clean power from the sun, wind, and small-scale hydro, plus the growing efficiencies we've achieved through conservation, there is no reason to go through a lengthy, expensive, and fraught process," he said. "We can meet our energy needs without this."

In response, Calomino said that this project could very well call for the use of the same renewable energy sources cited by Horowitz. Other missions conducted in the future may require them as well, but there are unique challenges to operating in space that may make using renewable energy sources impractical, if not impossible.

"These missions could call for a variety of solar, battery, radioisotope and fission power systems to enable a wide range of demanding requirements," he said. "Fission surface power is necessary in places where solar power, wind and hydro power are not readily available. On Mars, for example, the sun's power varies widely throughout the seasons, and periodic dust storms can last for months. On the moon, the cold lunar night lingers for 14 days, while sunlight varies widely near the poles and is absent in the permanently shadowed craters. In these challenging environments, power generation from sunlight is difficult and fuel supply is limited. Fission surface power offers a lightweight, reliable and efficient solution."

Steve Melink, the author of Fusion Capitalism: A Clean Energy Vision For Conservatives, and founder and CEO of Melink Corp., a company that promotes renewable energy for the commercial building industry, said that there were other factors to consider as well.

"When, not if, something goes wrong, how will we fix the problem, especially if it is an urgent one?" he asked. "Nuclear power is so complicated that anticipating every foreseeable problem will require parts, technicians, and supplies that would not seem feasible for generations to come."

He recommended that NASA use solar photovoltaics, which he said are already being used in space to generate power, and which he described as a practical solution.

Fission surface power is necessary in places where solar power, wind power, and hydro power are not readily available.
 Anthony Calomino
NASA's nuclear technology portfolio lead within the Space Technology Mission Directorate

"The cost has come down so much in the last 10 years that utilities, businesses, and schools everywhere here on Earth are installing it over other available options," he said of solar photovoltaics. "There are no catastrophic risks like meltdowns, radioactive contamination and complete power failures. Solar is the ultimate solution to ensure redundancy and expandability over time."

Despite these concerns, Calomino said that safety has been NASA's priority all along. The project still has to undergo the National Environmental Policy Act's approval process, which includes evaluating the project's environmental effects, and the power system will be designed so that nuclear fuel will not even be activated until it's on the moon's surface.

"Unlike terrestrial reactors, there is no intention for fuel removal or replacement," he said.

Calomino said that at the end of its 10-year mission, there's also a plan to retire the facility safely.

"At the end of life, the system will shut down, and radiation levels will gradually diminish to safe levels for human access and handling," he said. "The used systems could be moved to a remote storage location where they would not pose any threat to the crew or environment."

An artist's conception of a human Mars base, with a cutaway revealing an interior horticultural area
Source: NASA

Dr. Jose Morey, chief medical innovation officer at Liberty BioSecurity, said that even if there's an incident at the facility on the moon, it poses little risk to Earth. This is because the planet is protected by an atmosphere that blocks out the sort of deadly radiation generated in outer space.

"There are various forms of radiation, and cosmic rays are some of the most deleterious, and the universe is awash in it," he said. "There are also all other forms of radiation abundantly found throughout."

Dr. Morey added that some of the companies that have expressed interest in participating in this effort include Blue Origin, and BWXT. Blue Origin would not provide a comment to CNBC, and BWXT did not return requests for comments.

"It is a mix of general energy engineering companies, traditional aerospace companies, and new aerospace players as well," he said.

While this endeavor is only in its opening stages, it suggests that the nuclear energy industry is still exploring new frontiers. Despite the complex political nature of the nuclear power issue, Dr. Morey said that its advantages make it ideal for powering U.S. efforts in space.

"Nuclear energy has always been a very clean form of energy and extremely effective," he said. "Realistically, it will be pivotal to deep space exploration, and more importantly, to humanity becoming a multi-planetary species. This new dawn of space exploration will see a resurgence in the nuclear industry until the next form of efficient, clean energy is discovered."