Recently, NASA and the United States Department of Energy put out a call for industry to propose designs for a nuclear power plant that could be deployed on the moon within the decade, according to Science Alert. In the meantime, Interesting Engineering reports that China has completed a design for its own lunar-based nuclear reactor. The two news items suggests that both sides of the current space race are very serious about returning to the moon and developing Earth's nearest neighbor in a big way.
The Chinese lunar nuclear reactor is described as being capable of generating a full megawatt of electricity. According to Live Science, NASA requires that the lunar nuclear power plant generate just 40 kilowatts of power for 10 years, fit inside a 12-foot long by 18-foot-wide rocket, and weigh no more than 13,200 pounds. Presumably, if the moon base requires more than 40 kilowatts of power, more power plants can be launched and deployed ready for use.
By going nuclear, both NASA and the Chinese recognize that an immense amount of power is required to operate in space in a big way. The systems that keep astronauts alive and keep their experiments running require power; the more astronauts; the more power. If one adds systems that support commercial activities, such as lunar mining, then the proper conclusion is that solar alone is not the answer. Nuclear power is the key to opening space to a wide variety of human activity, for both scientific exploration and commercial development.
Nuclear power also has the advantage over solar power, whether space based, or Earth bound, in that it runs 24/7. Solar power systems need battery backups when sunlight is blocked.
NASA is also studying nuclear power for spacecraft, especially those that would voyage to Mars and points beyond. The space agency has considered nuclear rockets since the Nuclear Engine for Rocket Vehicle Applications (NERVA) program in the 1960s. NERVA ended when it became clear that NASA would not send humans to Mars any time soon. Now that Mars is back on the agenda, nuclear rockets, which would use a nuclear reactor to superheat exhaust from the back of a spacecraft, are also back.
A nuclear thermal rocket could send humans and their supplies to Mars much more quickly than a spacecraft with conventional rocket engines. Thus, astronauts voyaging to Mars will spend less time exposed to the radiation-drenched environment of deep space.
Just as nuclear power is experiencing a renaissance for space operations, the technology is being given a second look on Earth. Nuclear power has gotten bad press after high-profile accidents at Three Mile Island, Chernobyl and Fukushima. More enlightened environmentalists have concluded that nuclear power should be part of a solution that transitions human civilization away from dependence on fossil fuels.
Bill Gates, the billionaire philanthropist and co-founder of Microsoft, is partly financing a nuclear power plant that uses new technology to be built in Wyoming by 2028. The nuclear power plant will use liquid sodium instead of water to cool the reactor. The technology reduces the risk of an explosion or a meltdown. It also produces less nuclear waste.
Modern civilization, whether on Earth or in space, requires an immense amount of energy to operate. As technology advances, civilization will require even more power. Nuclear technology is available in the near term to provide that power, whether to run air conditioners in homes on Earth or to keep environmental systems operating on a lunar base or a spacecraft voyaging to Mars.
Will environmentalist opposition arise against nuclear systems in space as it has on Earth, inhibiting their development? Antinuclear activists have protested rocket launches that included fissile material, as they did in 1997 when the Cassini space probe launched with 72 pounds of plutonium 238 that provided power for its mission to Saturn. No doubt similar protests can be expected when a nuclear reactor and its fuel are launched to the moon.
However, as the Bulletin of the Atomic Scientists pointed out, once nuclear power plants are deployed in space, either at a moon base or on a spacecraft voyaging to Mars, they would present no danger to humans on Earth. The debate over nuclear power in space will occur, just as it has on Earth and will have to be engaged.
Mark R. Whittington is the author of space exploration studies "Why is It So Hard to Go Back to the Moon?" as well as "The Moon, Mars and Beyond," and "Why is America Going Back to the Moon?" He blogs at Curmudgeons Corner.