Google Inc. and SunPower Corp. are creating a $250 million fund to finance rooftop solar systems that will be leased to homeowners.

Google will contribute as much as $100 million and SunPower will chip in as much as $150 million, the companies announced. SolarPower, which already has lease arrangements with about 20,000 homeowners, said the program should be able to finance thousands of new rooftop systems.

Third-party ownership of solar systems is a fast-growing segment of the market, Greentech Media reports. Homeowners who sign leases with companies such as SunPower don’t have to pay the upfront costs of an installation while reducing their utility bills.

SunPower and Google will get the 30% investment tax credit and accelerated depreciation, Utilitydive.com says.

SunPower said the new agreement, which was announced on April 23, was Google’s third residential rooftop solar investment and its 16th renewable energy investment overall. Taken together, the company’s $1 billion investment paid for projects with a total capacity of more than 2 gigawatts, enough to power about 500,000 homes.

Utilitydive.com said that unlike solar providers SolarCity and Clean Power Finance, SunPower is a vertically integrated company that manufacturers and installs the panels and also handles of maintenance.