This is a very late game tech item for the Advent. It recharges antimatter stores for their Frigates and Capital ships. It can be upgraded to restore more antimatter. For the Advent Rebels, the Temple of Renewal can be upgraded to recharge the shields of a single target over time.
Very useful for the overall utility of the fleet. Place down one of these to charge the Antimatter of your Disciples to have them serve as a battery for your capital ships and support frigates. These should be placed around static defenses so this building is not sniped as the AoE Antimatter restore is invaluable. Also if you serve as an Advent Rebel you aquire a Shield Restoration ability for the Temple of Renewal very good when combined with Repair Platforms in keeping buildings and important frigates in working condition.