Hey Rich-
I have 3 hens and about a half acre. When I started letting my ladies out, it was only for a couple of hours at a time. I found that not only did they not have any interest in wandering far, but they moved around the yard together. Ultimately I did fence in my yard so I am more comfortable leaving them unattended for long periods of time. When it is time for them to head back to the coop (during the day) I can just walk behind them and shoo them toward the coop. They happily run inside. As far as night goes, the will put themselves to bed at dusk if you have not put them in yet. Instinct does all of the work. For the first week or so you may have to help them out. I think I pushed through the door from the run into the coop about a half dozen times. Now they do it on their own every night.
Good luck.
PS-
I have not used solar powered accessories. Just ran an extension cord to the coop yesterday for a light / heat source. I use a bottle with a nipple waterer. I am planning on having a couple and rotating it in the morning and at night to keep it thawed out.