Successful testing of fission reactor for future space exploration

NASA

NASA has demonstrated that its prototype nuclear fission reactor can operate safely and produce the power required for future space missions.

The Kilopower project aims to design a reliable fission reactor capable of providing space missions with kilowatts of power. The prototype system uses a solid cast uranium-235 reactor core, and the heat is transferred via sodium pipes to Stirling engines which then convert the heat to electricity. “Kilopower gives us the ability to do much higher power missions, and to explore the shadowed craters of the Moon,” said Marc Gibson, lead Kilopower engineer at the Glenn Research Center. “When we start sending astronauts for long stays on the Moon and to other planets, that’s going to require a new class of power that we’ve never needed before.”

The Kilopower Reactor Using Stirling TechnologY (KRUSTY) test that took place at the NNSA’s Nevada Security Site from November 2017 until March 2018 demonstrated that the 1 kW prototype is fully functional. “We threw everything we could at this reactor, in terms of nominal and off-normal operating scenarios, and KRUSTY passed with flying colours,” said David Poston, chief reactor designer at NNSA’s Los Alamos National Laboratory.

The experiment was conducted in four phases. The first two phases confirmed that each component operated correctly, without using any power. The power was then increased incrementally during the third phase, and the final phase was a full power test that lasted 28 hours, simulating reactor startup, rampup to full power, steady operation, and shutdown.

The team also simulated power reduction, failed engines, and failed heat pipes, showing that the system could handle multiple failures. “We put the system through its paces,” said Gibson. “We understand the reactor very well, and this test proved that the system works the way we designed it to work. No matter what environment we expose it to, the reactor performs very well.” 

The successful KRUSTY tests pave the way for the technology to be upscaled to produce 10 kW of power, which could be used to power crewed missions to Mars, enable long duration stays on the Moon or Mars, and improve robotic deep space travel.

Read more about the Kilopower project here.