Power rod

Power rods were mysterious crystalline formations that grew in the cavern of Haven Base on Arbra. They perpetuated huge amounts of energy and released harmless bolts of lightning. They were the main source of energy on which the Hoojibs fed. They also served as the power supply for the Rebels in Haven Base. Unfortunately, the heat they generated also attracted a slivilith.

Luke Skywalker believed they were powered by the Force. When the self-perpetuating force screen, the Grotto City, and the Darker were destroyed, Luke was afraid the power rods had lost the source of their energy, and Rebel technicians were notified to monitor the rods' output for decrease.

Text and facts from the “Power rod” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.