Sunshine is not an issue where I live, we only get 8-9in of rain per year. I am east of the mountains. The issue is more of the trees on the trails and the amount of power I use during the night.I understand, I keep forgetting that on the N.W. west coast the sunlight is low to nil.
On another recent trip without my wife, I only powered my CPAP and a few cell phones. In the morning the battery was still near full charge. So demand vs. amount of sunshine time is the issue. I have not pulled the solar system off yet and won't till I have the other system fully installed. Then I can see what works better for me.