Been away a while and now back with latest stable.
So can I connect solar panel on the roof of my starting shelter to appliances below?
Kinda need to get this one cleared before setting up a more permanent base.
Are the sources of power besides solar panels or generators?
Yes, you can set up solar panels on the roof and connect it to an appliance grid on another Z level. There are now two kinds of solar panels: vehicle ones and rooftop ones, where you can create a rooftop panel from 4 vehicle panels. This means that looking for panels on roofs is a lot more useful than taking them from vehicles.
There are wind turbines and water wheels as additional power sources. Note that wind turbines have a tendency to be rather poor, due to weak winds.
Also note that although you can connect a water wheel several wold tiles away from your base the connection breaks down irregularly as things outside of the reality bubble can’t really be relied on.
There are other issues that haven’t been resolved, but it generally works to set up a roof top panel farm (probably less so during the winter). Note that solar panel efficiency has been reduced, and apparently there is fog for a third of every day in New England.