SpiderBot needs power to fire its weapons. To provide that power, the player must build a SpiderBot Core Charger. The Core Charger must then be fed a Lithium Coil via an adjacent hopper, which can include the hopper already placed next to the docking station.
After the coil is fully charged, the Power Core is automatically is inserted into SpiderBot, giving it 1000 power. The max amount of power per second (pps) used to charge the coil is 33.2 pps. A power supply equal or greater than 33.2 pps will charge the coil in 25 seconds. Mathematically it will take a total of 830 power over 25 seconds to give SpiderBot 1000 power.