Accumulator
An accumulator was an object which collected and stored any form of energy.

The insectoid ship encountered by the  in 2269 had wands which collected energy from motion, sound, light, heat, and every kind of energy around them. ()

While on the surface of Delphi Ardu IV in 2364, Geordi La Forge noticed that the whole planet served as a  accumulator. ()

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de: Akkumulator
Energy technology