As described in the MG model manual and MS encyclopedia, at the conclusion of the One Year War, the Federation opened the Gundam Development Project, aimed at creating mobile suits superior to those that Zeon had developed. The RX-78GP01 Gundam Zephyranthes was the first of three Gundam type mobile suit prototypes completed under this plan.
The RX-78GP01 was designed to be an adaptable mobile suit, able to operate under any condition on earth or in space; to that end its design is superficially similar to the other RX series Gundams. Unlike previous suits, this was one of the first to re-introduce the core fighter concept in its design, utilizing the recently developed FF-XII Core Fighter II as the cockpit. The RX-78GP01 was taken to Australia's Torrington Base for terrestrial testing, where it was commandeered by (and later assigned to) Federation ENS (later LTJG) Kou Uraki in his effort to retrieve the RX-78GP02A.
One major innovation in the RX-78GP01's arsenal was the addition of a beam rifle that used removable energy capacitor clips called e-pacs. Previous beam rifle designs had the energy capacitor integrated into the rifle directly, resulting in the rifle becoming dead weight once the capacitor was depleted. With e-pacs, beam rifles can be used indefinitely as long as the pilot has a ready supply of replacement e-pacs. The RX-78GP01 has three e-pacs (one mounted on the rifle, two held in reserve on the shield) in its normal deployment configuration.
Gundam Development Project. (2006, December 3). In Wikipedia, The Free Encyclopedia. Retrieved 15:58, December 3, 2006, from http://en.wikipedia.org/w/index.php?title=Gundam_Development_Project&oldid=91798081