It is well established in Stargate lore that a Stargate needs power to dial out initially, which usually comes from the DHD. What powers dialing out for the seeded Stargates in Stargate Universe?

Edit: First potential theory: The power source is located in the Stargate itself. I have two issues with this (based on some facts and some personal logic)

1) Seeded Stargates in Universe are built using materials harvested on the planet they build the gate on. If the amount of Naquadah needed to build thousands of not hundreds of thousands of gates was too high and this method was chosen instead, the same would be likely for the power sources. That would mean that the power sources, like the gates would be more crude. It seems unlikely they would have been able to last for millions of years without losing power.

2) If they did initially had power sources in the Destiny gates, why switch later on for the Milky Way gates? DHDs are much more fragile than Stargates so it would make sense to have the power sources stay where they were.