Aerospace and Defense

NASA Proves Nuclear Fission System Fit to Fly

03 May 2018
Artist's concept of new fission power system on the lunar surface. Source: NASA

Testing on a kilowatt-scale nuclear reactor that could serve as the power source for crewed missions on Mars, the Moon or other extraterrestrial destinations was initiated by NASA and the U.S. Department of Energy in November 2017. Kilopower is a small, lightweight fission power system capable of providing up to 10 kW of electrical power, sufficient to supply several average households continuously without refueling for at least 10 years. For NASA missions, four Kilopower units would provide enough power to establish an outpost and provide onboard lighting, water and oxygen.

Now the agency, in collaboration with the U.S. Department of Energy’s National Nuclear Security Administration (NNSA), reveal the results of the Kilopower Reactor Using Stirling Technology (KRUSTY) experiment conducted at the NNSA’s Nevada National Security Site. The evaluations were designed to demonstrate full functionality of the reactor works and that it is safe under abnormal circumstances. Two tests were conducted without the reactor generating power to test the components and a third increased power in stages. The final trial was a 28-hour, full-power mission simulation that included reactor startup, ramp to full power, steady operation and shutdown.

Kilopower was confirmed to operate and handle multiple failures during simulated power reduction, failed engines and failed heat pipe events.

The prototype power system uses a solid, cast uranium-235 reactor core, about the size of a paper towel roll. Passive sodium heat pipes transfer reactor heat to high-efficiency Stirling engines, which convert the heat to electricity.

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Discussion – 3 comments

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Re: NASA Proves Nuclear Fission System Fit to Fly
2018-Jun-23 12:50 AM

What is the cost of a 10 kW KRUSTY and what is its useability on Earth? How is it beneficial to a SpacePlace or Kids Space environments?

Re: NASA Proves Nuclear Fission System Fit to Fly
2018-Jun-23 1:14 AM

What is the purpose of a Deep Space Mission using Nuclear Fission to find a location for KRUSTY to provide 10kW of power to look for and obtain water in outer space for a Space Station?

Re: NASA Proves Nuclear Fission System Fit to Fly
2018-Jul-26 9:27 PM

I hope there is a prototype somewhere racking up as many hours as possible so we can find out if the [more?] complex stirling engine has any unknown [early?] breakdown modes. Piston seals? Knuckle bearings?

Sodium heat pipes may also have a corrosion limited operating lifespan. Is there a current application that shows us how long these things operate without leaking?

Im all for the stated application. But if power goes down on a space ship or space station or exo-colony, life support long as the batteries.

Reliability Engineers will earn their wings on this project. Get your combs out and start looking for what was overlooked. I will sign up to help.

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