Hi Carrie,
The average home is not built or operated with efficiency in mind. This makes powering them expensive, even from "conventional" sources. With a solar powered home, we need to pay close attention to the appliances and make sure they are efficient. When we do this, we find that solar is not that expensive. Still, unless you are lucky and live in a place where there are incentives for solar, the upfront cost keeps a lot of homeowners from making the switch.
I agree that the best way to go solar is to stay on the grid and feed back clean energy. Then the grid is used like a "lossless battery", which is far more efficient than going "off-grid". Plus when solar energy is fed back to the grid, it helps offset energy that would otherwise be produced with a dirtier source. It also helps in sunny places, (where air conditioning loads are great), by producing electricity at a time when the utility struggles to keep up with demand - thus decreasing the likelyhood of summertime brownouts.
Blessings,
Kelly