I don't usually take interest in these schemes because in the end, someone expects to make a lot of money, and someone else is expected to pay for the party...In this case, my pre-suppositions would have been right...
A Sunrun customer service representative told me that in the year before he went solar, Jug’s monthly bill to Southern California Edison averaged $115. Under the terms of his deal, he paid $75 a month to Sunrun. The panels on his garage were expected to cover 85 percent of his energy needs. That left him reliant on SoCal Edison for the remaining 15 percent, at a cost of about $17 a month. All in, his energy bills came to about $92, a savings of about $23 a month.

I got ahold of a copy of Jug’s contract, and quickly saw how Sunrun could afford to extend such an offer. It lasted 20 years. The payments escalated annually by 2.9 percent—they’d be 72 percent higher by 2036. The tax credit was worth at least $5,000.
The tax credit mentioned went to the solar panel company, not the homeowner...I'm all in favor of ways to conserve resources when they actually benefit the consumer...This one didn't......Ben