The covered pick-ups will help restore supplies of electricity to five million customers around the central network region.
Nissan worked with ATT Papworth and van racking specialist Edstrom to ensure the vehicles met Central Networks' standard.
ATT built a special lockable top to make the pick-up secure, while Edstrom kitted out each with a range of racking and shelving. Towbars mean the Navaras can also tow generators.
Central Networks expects the new pick-ups to do 20,000 mile s a year for four years.