An Orbital Defense Generator, or ODG, is a large groundside power plant used to provide the energy needed by Orbital Defense Platforms to fire their Magnetic Accelerator Cannon.^[1]

Prior to the Fall of Reach, Reach had seven ODGs to power twenty ODPs. As demonstrated during the battle, ODGs were vulnerable to ground assault, and the failure of UNSC ground forces to protect the power plants and the resulting nullification of the planet's ODPs was a major factor in the battle's outcome and resulted in the loss of Reach. There were also ODGs on Earth to power the Orbital MAC guns.^[1]

The only known ODG facilities are the Orbital Defense Generator Facility A-331 and Orbital Defense Generator Facility A-412 on Reach.

SpeculationEdit

Although never explicitly elaborated upon, it seems likely that the means of power transmission from the ODGs on the ground to the ODPs in orbit was through a means similar to rectennas, a form of a high powered antenna.

Sources Edit

1. ↑ ^{1.0 1.1} Halo: First Strike, page ??