Hamilton Sundstrand and Proton Energy Systems have won contracts from the US Defense Advanced Research Projects Agency to develop water-based propulsion technologies for spacecraft.

The $4.9 million 12-month contracts call for the development of a water-based reversible fuel cell that also operates as an electrolyser, to improve spacecraft manoeuvrability and extend its life. When the craft is exposed to sunlight, the stack is an electrolyser, converting water into hydrogen and oxygen, which can be used for rapid manoeuvring. Slower manoeuvring is provided by water used as a propellant in electric thrusters. In the shade, stored hydrogen and oxygen are converted back to water to generate electricity.

One company will win a two-year contract next year, leading to a space demonstration.

Source: Flight International