A Cold Fusion Reactor Core is the power source used by Dial Home Devices. (SG1: "The Fifth Race") Developed by the Ancients, these power sources are incredibly robust, being able to provide power to their respective Stargate for as long as 50 million years before becoming depleted (SG1: "Frozen"). Though they can easily provide enough power to dial an in-galaxy address, they do not supply nearly enough power to establish an intergalactic wormhole.
- The name "Cold fusion reactor core" originates from a screenshot of the DHD schematics Col. O'Neill drew in the episode The Fifth Race. On the schematic, the final step in the process to fix the DHD, step "E", reads, in part: "Now you are ready to turn the power on again. The DHD has a cold fusion reactor core. It will take a few minutes to be fully charged".