We used a popup for 30 years. It had a little furnace but we didn't use it much because it was noisy and we are not very far north, just at the start of the Alaska Highway. We had no battery in the trailer for most of the time - I ran a 16 gauge pair of wires to the van battery so we could run the furnace OR the lights. We killed the van battery a couple of times over the years and got boosts from other campers. Later on I carried a jumpstart battery which I plugged into the cigarette lighter when driving and into the popup when we were camping.
Now if you have a TV in your popup, you will need a lot more power. Maybe carry some non-electric entertainment items to cut down on its needs. I agree about avoiding generators; they are very noisy for tent campers - and smelly.
