Power is just below food and water in terms of necessities required to maintain a colony. With each new addition and building, more power is required to maintain them. Power Generators are used to provide the needed energy to keep the day to day functions of a colony on track. Utilizing state of the art nuclear fusion energy to provide clean and stable power sources, these generators can be upgraded and modified to produce even more energy should the need arise.
Although no longer an issue, the first prototypes of Power Generators were subject to power spikes, which could result in sub-atomic explosions and radioactive fallout. Modern Power Generators utilize automated power inhibitors to ensure that surges are no longer an issue, though these buildings are still vulnerable to a direct attack.