In short: Plug-in solar costs far less than rooftop solar: typically a few hundred dollars for a small kit, rather than the tens of thousands a rooftop system can run, with nothing to finance and no installer to pay. Because Bright Saver is a nonprofit, our members buy the exact same kits at cost, with no markup, for a $29 a year membership. That combination makes it one of the most affordable ways to start generating your own power. If you are pricing out home solar, plug-in