Why would you have a Solar panel but nothing else?
I use Solar but I carry solar because I carry devices needing power.
I would say if I were to be dropped on a desert island and I had a choice things to bring, then I'd bring this lot:
- an LC40 so I can see at night
- a Powercore 10000 to keep going through bad weather / winter when solar less often
- a very very large storage phone type device. e.g. My phone has 256GB storage but probably add some high capacity storage and OTG cable. I'd then prepare by downloading loads and loads of videos for offline viewing.
- Soundbuds Life.
- a good quality waterproof bag, if not two to handle moving in rain storms.
I do see the idea of making a spark but there is no need, a knife is all you need typically, flint+stone and you wait for a dry period and then make tinder, and you keep that tinder away from damp and then strike the knife over the stone to make a spark on the tinder so you can make fire fairly easily if you are able to begin with dry stuff. If you had no knife then find a harder type of stone and throw it against rock to make a sharp object, then use that to make sharper objects. If you had a permanent home you'd keep a fire going continually away from rain and the fire is drying out the next set of fuel nearby to then be used as fuel. It is not complicated, our ancient forgotten ancestors figured that out. We used fire to then store calories from excess food into typically winter, we'd dry out food, salt it e.g. find a sea-facing flat-ish area and then separate it off to make a salt-flat and let summer heat evaporate off water and then the salt left we steadily hoard, or we use wood to boil seawater, that salt then preserves meat in excess periods to use in otherwise famine periods. Fire also smokes food (fish, etc). We then use yeast to convert excess carbohydrates into beer which is preserves them from vermin. Hence you get smoked fish, corned beef, beer. When you combine the fact that humans evolved to basically be able to live at 100Lb of weight up to 300Lbs of weight to store energy within out bodies, is how we got here (not extinct).
Probably the hardest part is that the human has in one organ the weakest part and the strongest part. A human can think itself out of a problem but also if left alone can think itself into a problem too (worry, depression, make up myths like gods).
I just did a 4 days off-grid and I did verify I can keep everything fully charged with solar and from that I am doing a 3 weeks off-grid next month.