I have had 2 different portable folding solar panels. The first was 40 watt. Just had LED lights
to run, and charging phone or laptop. Size fit side of closet so I had an option to attach it to that wall. With a furnace
, and newer fridge
that uses some power even on propane
and a water pump I bought a 100 watt.
I think the biggest issue is how sturdy the legs are. The 40 watt I felt the legs were very light weight
and required more care. The 100 watt was a bit more solid. When reading reviews look for reviews with feedback on the legs.
In addition to considering size and knowing where you can store it pay attention to weight
. A 100 watt panel with controller isn't terribly heavy but it isn't light weight
either. Sturdier legs and frame will add weight. I can handle ours, my fairly small wife wouldn't be able to.
Plus 1 on using contractor grade #12 extension cord if you want to have a longer lead. I went with portable because as much as if I can I will park in shade. My hitch plug charges from tow vehicle when driving so I expect to arrive in camp fully charged. So I don't gain on the road charging from a roof mount.
They make SAE 12 volt plugs that are widely available. Amazon to Walmart. Or marine store if you want to pay top dollar. They are a red & black wire 12 volt plugs that only go together one way. Common use is for battery to trolling motor. These are good for making connections for portable solar.
I cut off the battery clamp from the solar suitcase cord, added the SAE plug, put an SAE on the battery that comes out just under the battery cover. Making a nice weather tight, can't do it backwards connection.
I also added an SAE connector to the battery clamps wire I cut off originally, so I preserve the ability to use those original clamps if needed. Charging car battery for example. I did once kill the battery while camping. Got a jump but I was in a state park, boondocking I would probably been forced to use solar.
to keep camper 48* F at night, cloudy day and 100 watt panel had no trouble taking the battery up to full charge. I haven't tried to see if 100 watt could keep up with running the furnace
during the day to maintain more comfortable temperature and replace the night use. I also re-positioned the panel 3 or 4 times during the day to keep it aimed at the sun.