Going to need some additional information. How long will the pump run at one time? If you're looking at 1/2 hp (roughly 375 watts). It will probably be prohibitively expensive to run the pump directly from solar panels, 375 watts of solar is going to run you some serious $$. Add to that the fact that you'll only get 4 or so hours of sunlight on good days. Even adding tracking to the solar panels will only extend that an hour or so.
So, start out by telling us how long and how often the pump is expected to run. If you're going to be manually moving the pump from well to well, you'll probably want to go with a combination of solar panels and batteries. At that point, is it that much more cost effective/convenient then what you're currently doing? Maybe explain why the current system is unacceptable.