Fuel cell power systems have provided electrical power on several NASA programs since its founding, from Gemini to Apollo to the Space Shuttle. The combined benefits of only needing a tiny fraction of the hydrogen and oxygen present in the propellant tanks to provide kiloWatts of power and producing high purity, potable water as a reaction product made fuel cell systems a valuable technology for long duration, manned spaceflight.
When the Space Shuttle program ended, the fuel cell production line was discontinued, leaving NASA and private space companies without a space-qualified fuel cell system to support long duration manned space activities. The combination of solar panels and batteries provide power for almost all satellites and manned spacecraft today, but are limited by how much energy they can store, struggle to sustain power while the sun is blocked, and do not produce water for use by the astronauts.