There are many companies doing just this (sunrun, solarcity, etc). There's currently some loophole that as a business they get paid more for their electricity than a homeowner would (due to subsidies to encourage businesses to use solar). So they get a price that you alone could not get. I think that's why it works.
bigethan -- that's not necessarily how it works. It does work differently in different state & local markets, so it's possible that there's a market that works that way. I don't know of any, personally.
Usually the deal is something called a PPA -- Power Purchase Agreement. It's usually set up that you agree to pay some fixed price-per-kWh, and that price escalates by some regular way over the life of the contract. That price could be higher, or lower, than the prevailing rates for electricity in that market, and that escalator could be higher or lower than rates at which energy prices increase -- but either way, they're locked in from the start.
There's no "loophole" - but the US tax code doesn't all you as a homeowner to use the accelerated depreciation deduction the way a third party for-profit business can if they own the system and lease it to you or sell you the power it produces.
