Archive | Nuclear Systems RSS

Kilopower: What’s Next?

When astronauts someday venture to the Moon, Mars and other destinations, one of the first and most important resources they will need is power. A reliable and efficient power system will be essential for day-to-day necessities, such as lighting, water and oxygen, and for mission objectives, like running experiments and producing fuel for the long journey home.

That’s why NASA is conducting experiments on Kilopower, a new power source that could provide safe, efficient and plentiful energy for future robotic and human space exploration missions.

This pioneering space fission power system could provide up to 10 kilowatts of electrical power — enough to run two average households — continuously for at least ten years. Four Kilopower units would provide enough power to establish an outpost.

About the Experiment
The prototype power system was designed and developed by NASA’s Glenn Research Center in collaboration with NASA’s Marshall Space Flight Center and the Los Alamos National Laboratory, while the reactor core was provided by the Y12 National Security Complex. NASA Glenn shipped the prototype power system from Cleveland to the Nevada National Security Site (NNSS) in late September.

The team at the NNSS recently began tests on the reactor core. According to NASA Glenn’s Marc Gibson, the Kilopower lead engineer, the team will connect the power system to the core and begin end-to-end checkouts this month. Gibson says the experiments should conclude with a full-power test lasting approximately 28 hours in late March.

The Kilopower advantage
Fission power can provide abundant energy anywhere we want humans or robots to go. On Mars, 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.

“We want a power source that can handle extreme environments,” says Lee Mason, NASA’s principal technologist for power and energy storage. “Kilopower opens up the full surface of Mars, including the northern latitudes where water may reside. On the Moon, Kilopower could be deployed to help search for resources in permanently shadowed craters.”

In these challenging environments, power generation from sunlight is difficult and fuel supply is limited. Kilopower is lightweight, reliable and efficient, which makes it just right for the job.

For more information about the Kilopower project, visit:

Read Full Article

Continue Reading

Powering Up NASA’s Human Reach for the Red Planet


Credits: NASA Glenn Research Center

NASA is pushing forward on testing a key energy source that could literally “empower” human crews on the Mars surface, energizing habitats and running on-the-spot processing equipment to transform Red Planet resources into oxygen, water and fuel.

The agency’s Space Technology Mission Directorate (STMD) has provided multi-year funding to the Kilopower project. Testing is due to start in November and go through early next year, with NASA partnering with the Department of Energy’s (DOE) Nevada National Security Site to appraise fission power technologies.

Confidence builder
“The Kilopower test program will give us confidence that this technology is ready for space flight development. We’ll be checking analytical models along the way for verification of how well the hardware is working,” explains Lee Mason, STMD’s principal technologist for Power and Energy Storage at NASA Headquarters.


Credits: NASA Glenn Research Center

The DOE/National Nuclear Security Administration infrastructure and expertise have been instrumental, Mason points out, as have the talents of Los Alamos National Laboratory engineers in New Mexico. NASA’s Glenn Research Center in Cleveland has managed all phases of the Kilopower Project, from designing and building the hardware, with contributions from NASA’s Marshall Space Flight Center in Huntsville, Alabama, through developing the test plan and operating the tests. The Y12 National Security Complex in Oak Ridge, Tennessee is providing the reactor core.

“A space nuclear reactor could provide a high energy density power source with the ability to operate independent of solar energy or orientation, and the ability to operate in extremely harsh environments, such as the Martian surface,” notes Patrick McClure, project lead on the Kilopower work at the Los Alamos National Laboratory.

“The reactor technology we are testing could be applicable to multiple NASA missions, and we ultimately hope that this is the first step for fission reactors to create a new paradigm of truly ambitious and inspiring space exploration,” adds David Poston, Los Alamos’ chief reactor designer. “Simplicity is essential to any first-of-a-kind engineering project – not necessarily the simplest design, but finding the simplest path through design, development, fabrication, safety and testing.”

Sun-independent power
The pioneering Kilopower reactor represents a small and simple approach for long-duration, sun-independent electric power for space or extraterrestrial surfaces. Offering prolonged life and reliability, such technology could produce from one to 10 kilowatts of electrical power, continuously for 10 years or more, Mason points out. (The average U.S. household runs on about five kilowatts of power). The prototype power system uses a solid, cast uranium-235 reactor core, about the size of a paper towel roll. Reactor heat is transferred via passive sodium heat pipes, with that heat then converted to electricity by high-efficiency Stirling engines. A Stirling engine uses heat to create pressure forces that move a piston, which is coupled to an alternator to produce electricity, similar in some respects to an automobile engine.

Having a space-rated fission power unit for Mars explorers would be a game changer, Mason adds. No worries about meeting power demands during the night or long, sunlight-reducing dust storms. “It solves those issues and provides a constant supply of power regardless of where you are located on Mars. Fission power could expand the possible landing sites on Mars to include the high northern latitudes, where ice may be present,” he points out.

Power options
NASA has flown a number of missions powered by radioisotope thermoelectric generators (RTGs) over the past five decades, such as onboard the two Viking Mars landers, the Curiosity rover now at work on the Red Planet, the Apollo expeditions to the moon, the two Voyager spacecraft, and the New Horizons probe to Pluto and beyond, as well as the just-concluded Cassini mission at Saturn. RTGs produce electricity passively with no moving parts, using the heat from the natural decay of their radioisotope heat source.

“What we are striving to do is give space missions an option beyond RTGs, which generally provide a couple hundred watts or so,” Mason says. “The big difference between all the great things we’ve done on Mars, and what we would need to do for a human mission to that planet, is power. This new technology could provide kilowatts and can eventually be evolved to provide hundreds of kilowatts, or even megawatts of power. We call it the Kilopower project because it gives us a near-term option to provide kilowatts for missions that previously were constrained to use less. But first things first, and our test program is the way to get started.”

The novel energy-providing technology also makes possible a modular option for human exploration of Mars. Small enough in size, multiple units could be delivered on a single Mars lander and operated independently for human surface missions.

Breadboard test
In step-wise fashion, with safety as a guiding principle, Mason says the Kilopower hardware will undergo a full-power test lasting some 28 hours.

Moving the power system from ground-testing into a space system is an achievable objective, says Don Palac, Kilopower project manager.

Lead Researcher Marc Gibson adds, “The upcoming Nevada testing will answer a lot of technical questions to prove out the feasibility of this technology, with the goal of moving it to a Technology Readiness Level of 5. It’s a breadboard test in a vacuum environment, operating the equipment at the relevant conditions.”

Looking into the future, Mason suggests that the technology would be ideal for furthering lunar exploration objectives too. “The technology doesn’t care. Moon and or Mars, this power system is agnostic to those environments.”

NASA is pursuing development and research of the Kilopower project in order to meet the agency’s anticipated future planetary surface power needs. The objective of NASA Space Technology Mission Directorate’s Kilopower project is to demonstrate space fission power systems technology to enable crewed surface missions on planetary bodies. Credits: NASA

Read Full Article

Continue Reading

Researchers Test Novel Power System for Space Travel – Joint NASA and DOE team demonstrates simple, robust fission reactor prototype

CLEVELAND – A team of researchers from NASA’s Glenn Research Center in Cleveland and Los Alamos National Laboratory in Los Alamos, N.M. have demonstrated a new concept for a reliable nuclear reactor that could be used on space flights.

On September 13, the research team demonstrated the first use of a heat pipe to cool a small nuclear reactor and the first use of a Stirling engine to convert the reactor heat into electricity. The test was conducted at the Nevada National Security Site’s Device Assembly Facility near Las Vegas. The Demonstration Using Flattop Fissions (DUFF) experiment produced 24 watts of electricity.

John Bounds

John Bounds of Los Alamos National Laboratory’s Advanced Nuclear Technology Division makes final adjustments on the DUFF experiment, a demonstration of a simple, robust fission reactor prototype that could be used as a power system for space travel. DUFF is the first demonstration of a space nuclear reactor system to produce electricity in the United States since 1965. Credits: Los Alamos National Laboratory

A heat pipe is a sealed tube with an internal fluid that can efficiently transfer heat produced by a reactor with no moving parts. Heat pipe technology was invented at Los Alamos in 1963 and is used widely by NASA for aerospace applications. A Stirling engine is a relatively simple closed-loop engine that converts heat energy into electrical power using a pressurized gas to move a piston within a magnetic field. Using the two devices in tandem allowed for creation of a simple, reliable electric power supply that could be adopted for space applications.

Researchers configured DUFF on an existing experiment, known as Flattop, to allow for the water-filled heat pipe to extract heat from uranium. Heat from the fission reaction was transferred to a pair of free-piston Stirling engines manufactured by Sunpower Inc., in Athens Ohio. Engineers from Glenn designed and built the heat pipe and Stirling assembly, and operated the engines during the experiment. Los Alamos nuclear engineers operated the Flattop assembly under authorization from the National Nuclear Security Administration.

DUFF is the first demonstration of a space nuclear reactor system to produce electricity in the United States since 1965. It confirms the basic nuclear reactor physics and heat transfer for a simple, reliable space power system.

“The heat pipe and Stirling engine used in this test are meant to represent one module that could be used in a space system,” said Marc Gibson, Glenn’s lead engineer for the test. “A flight system might use several modules to produce approximately one kilowatt of electricity.”

“The nuclear characteristics and thermal power level of the experiment are remarkably similar to our space reactor flight concept,” said Los Alamos engineer David Poston. “The biggest difference between DUFF and a possible flight system is that the Stirling input temperature would need to be hotter to attain the required efficiency and power output needed for space missions.”

A power system based on the concept demonstrated by DUFF could be attractive for future space exploration missions that may require significantly higher power levels than current systems can easily provide.

“Perhaps one of the more important aspects of this experiment is that it was taken from concept to completion in six months,” said Los Alamos engineer David Dixon. “We wanted to show that with a tightly-knit and focused team, it is possible to successfully perform practical reactor testing.”

Glenn’s contributions were made possible through resources provided by the NASA Radioisotope Power Systems Program Office within the Science Mission Directorate and the Nuclear Systems project under the NASA Office of Chief Technologist, Game Changing Development Program.

The Los Alamos participation in this experiment was made possible through Los Alamos’s Laboratory-Directed Research and Development Program and program office support.

For a print quality image of a test operator inserting the heat pipe into the reactor, visit:

For more information about Glenn, visit:

For more information about Los Alamos National Laboratory, visit:

NASA Glenn Research Center news releases are available automatically by sending an Internet electronic mail message to:
Leave the subject and body blank. The system will reply with a confirmation via e-mail of each subscription. You must reply to that message to begin your subscription.
To unsubscribe, address an e-mail message
Leave the subject and body blank.

Continue Reading