A power plant is required for all spaceships. The power plant on a spaceship consumes hydrogen to keep the ship's electric capacitors charged. The amount of electricty a ship can hold is determined by the amount of power plants a ship has. A basic spaceship , one with only a helm , fuel tank , life support , and gravity drives can run off only one power plant even if the ship has over 200 gravity drives at full throttle. More than one power plant are required if you want to use wormhole drives, shields, turrets, and weapon bays . The number of power plants determine how many times a ship turret or weapon bay can fire repeatedly before the capacitors need to recharge. Capacitors recharge constantly even if they are being used, so the number of consecutive shots in the ship specifications may actually be higher in practice.