Phoenix Logs/UNSC Buildings/Generator
From Halopedia, the Halo wiki
Each firebase has an integral power plant to meet immediate needs, but additional Generators are needed for the accumulation of Power used for unit assembly and purchase of upgrades. A Generator should be among the first support structures added to a new firebase. The Advanced Generator upgrade significantly improves Power output.
The older "pod" bases deployed by the Spirit of Fire used hydrogen-burning reactors for power, which required expensive and bulky fuel storage and safety systems. However, new firebase structures require far less power to function compared to the legacy designs, allowing Isabel to adapt modern UNSC vertical axis turbines as a more sustainable replacement.