What's commonly called "solar leasing" is now the most popular way for homeowners to install solar electricity.
A solar company installs the panels for the customer for free or for a minimal cost. Then it sells the consumer the electricity for about 10 percent less than local utility rates.
SolarCity CEO Lyndon Rive says this makes solar power accessible for the average homeowner.
RIVE: "Before solar was more designed to those who could afford a large upfront cost of $20,000 to $25,000. Now the average person can go solar and just start saving money, there's no investment."
The company pays for the equipment and maintenance -- and it pockets the profit over the 20-year period.
Rive says the option is so popular that in some markets his company has a waiting list of 4 to 6 months.
And now there's even more room for growth. The California Public Utilities Commission has changed regulations, extending the financial incentive for solar producers.