Lance sells their campers with a 95 Watt solar panel and this is good enough. I have two 100 Watt panels on my camper and it is overkill.
Unless you are in Alaska during the winter months you will have more than enough sunlight to recharge the battery. Solar cells have been designed for decades to work with much less than a 90 degree angle to the sun and still put out power.
A 100 AH battery is not going to be discharged more than 50% so 5 amps over 10 hours is the most you will need from the panel. I have never been able to use anything close to 50 AH overnight and that is in 100 degree and 24 degree weather and the use of the lights, the fridge, the furnace fan, water pump, and a 17" LCD TV.
We stay at a spot for 2-3 days and then travel to the next location. While driving the truck alternator is recharging the battery as well as the solar panels. The solar panels are starting to recharge the battey long before we hit the road and they continue to charge after we have stopped at our new location.
What none of the camper or other RV manufacturers provide is a good digital charge metering device like the ones from Trimetric. Spend the $200 to add one to the camper and then you can monitor usage and charge level accurately. Without this information you are guessing as to what is going out and back in and how effective the charging setups are for your pattern of use with your camper.
Lots of opinions but I have actually installed a digital meter and a solar panel charging system and have been using it for the past two years.
I put about the same amount of money into the solar setup as I would have put into adding a generator. Difference is that the solar is charging my batteries and keeping them at 100% every day of the year and I need do nothing. It is 100% automatic with nothing to start or refuel or shut off and nothing to get stolen or have breakdown on a trip, and no gas cans to carry around. It is also dead silent and the idea of traveling hundreds of miles to a pristine area and listening to the noise of a generator is not something that I find rational in the least.
