Electrical Power
The subsystem that generates, stores, and distributes electricity — from solar arrays or radioisotope generators, through batteries, to every instrument and heater on board.
Components
- BatteryComponent
Rechargeable batteries store energy from the solar arrays to power a spacecraft through eclipse, at night, or during peak demand. Lithium-ion has largely replaced older nickel chemistries.
- Fuel CellComponent
A device that generates electricity by combining hydrogen and oxygen, producing water as a by-product. Fuel cells powered the Apollo and Space Shuttle missions, useful for short crewed flights needing high power.
A nuclear power source that converts the heat of decaying plutonium-238 directly into electricity. RTGs let missions operate far from the Sun or through the lunar night — powering Voyager, Cassini, and the nuclear Mars rovers Curiosity and Perseverance (the earlier rovers were solar-powered).
- Solar ArrayComponent
Panels of photovoltaic cells that convert sunlight into electricity — the primary power source for most spacecraft in the inner Solar System. Beyond Jupiter, sunlight becomes too weak and other sources are needed.
Knowledge connections
- ContainsSolar Array
- ContainsBattery
- ContainsRadioisotope Thermoelectric Generator (RTG)
- ContainsFuel Cell
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.
- ESAEuropean Space Agency
European missions, observatories, and space science imagery.