If your house remains in the 70s it shouldn't be a problem. They can go a few days without lights if needed. Heat packs help but i usually don't bother with them outside of winter.
Hope you guys are all O.K and not too much inconvenience aside from the power outage ! Like Coop said, dragons are fine for a couple days without lights, but don't feed them as usual. It's harder on a baby or young juvie [ under 13" ] You can always take him outside if the yard is not soggy....if you have a large plastic tote you can set it up in part shade, be SURE it's part shade if the temp. outside is above 70, otherwise it will absorb the heat + raise the temp. too high. You can feed + hydrate him outside as usual if you allow for a few hours in the sun + heat.