I just spent two months CG hosting in a NP without hookups. I did have both solar and a generator. Also had a portable waste tank that I could tow to the dump station without moving the TT.
That said, one of the biggest "upgrades" that I made before the trip was to replace all the bulbs I normally used in the TT with LEDs. That significantly extended the length of time I could light the TT with the battery before recharge.
There were campers that stayed for days without a generator. Some of them would connect their TT to their TV occasionally and recharge their battery that way.
Enjoy your trip.