In Maine? There's certainly money in it. Well, for the installer at least. There's no way the HO will achieve energy payback on a solar panel in maine right now, so anyone putting in panels is doing so not for economics, but for ecological reasons and at the cost of these systems, it means they have money to burn! So charge double your rate for this specialty work and know that you're helping the environment, too
I'd be prepared to give a lot of estimates to sticker shocked people, though. For as much as solar is talked about, most people just have no idea how much solar costs for how little you get back.
Unless you live in a VERY sunny area with extremely high electricity costs, large government subsidy and time of use billing, solar doesn't make sense. A homeowner in southern California might actually save some money, but that's only because they're already paying an outrageous amount for their electricity. For someone like me in VA with 7 cents/kWh electric, a middling lattitude and a lot of cloudy days, even if I lived here 25 years, I wouldn't cover 1/3 of the installation cost. Solar water heating is economically viable in most of the country, but that's more of an issue for plumbers than sparkies. And even then, still wrought with problems.