Los Alamos tests new spaceship power system

Posted by Kate Taylor

Researchers at the Los Alamos National Laboratory have developed a  simple, robust fission reactor prototype that could be used as a power system for space travel.

Named - perhaps rather worryingly - DUFF, or Demonstration Using Flattop Fissions, it's the first time the US has demonstrated a space nuclear reactor system that produces electricity since 1965.

The research team for the first time used a heat pipe to cool a small nuclear reactor and power a Stirling engine at the Nevada National Security Site’s Device Assembly Facility near Las Vegas. The experiment produced 24 watts of electricity.

A heat pipe is a sealed tube with an internal fluid that can efficiently transfer heat produced by a reactor with no moving parts; and 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.

Using the two devices in tandem allowed for creation of a simple, reliable electric power supply that can be adapted for space applications, says the team.

"The nuclear characteristics and thermal power level of the experiment are remarkably similar to our space reactor flight concept,” says 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."

Current space missions typically use power supplies that generate about the same amount of electricity as one or two household light bulbs. Boosting available power could potentially increase the speed with which mission data is transmitted back to Earth, or the number of instruments that could be operated at the same time.

"A small, simple, lightweight fission power system could lead to a new and enhanced capability for space science and exploration”, says Los Alamos project lead Patrick McClure.

"We hope that this proof of concept will soon move us from the old-frontier of Nevada to the new-frontier of outer space."