Direct ownership of residential photovoltaic (PV) systems in the U.S. is poised to overtake third-party ownership in 2017 for the first time since 2011, a report from GTM Research says.

Third-party ownership, including leases and power-purchase agreements, accounted for 72% of all PV systems installed in 2014, but the numbers have been dropping since then as more customers bought solar arrays with cash or with a loan.

In 2015, third-party ownership dropped to 62% of all residential installations; that will dip to an estimated 54% this year. In five years, GTM expects that the fraction of residential systems bought outright will climb to 73%, a virtual mirror image of the situation in 2014.

The report points to several factors in explaining the trend. First, local installers are growing more quickly than big national concerns, such as SolarCity and Vivint Solar, which rely more heavily on leases than sales. Smaller installers are having more luck at cash sales as the cost of solar continues to fall. Finally, emerging markets such as Utah and Florida do not currently allow power-purchase agreements, so solar companies are forced to sell systems, the report says.

“The solar loan market is much more fragmented than the leasing market ever was,” said report author Nicole Litvak. Both installers and homeowners have access to more lenders, and more loan options, than in the past.

Growth rates, however, are slowing. GTM Research said that after four years of growth greater than 50%, the U.S. residential market will see a growth rate of only 16% this year.

Sales and loans help SolarCity

The growth of loan and cash sales was a big help to SolarCity, the country’s biggest solar installer, in the third quarter of the year, PV Magazine said. The company saw a 76% growth in revenue with loan and cash sales adding up to 23% of the installations it booked during the quarter (the company, however, still shows net losses).

Power-purchase agreements that furnish homeowners with solar systems at little or no upfront cost have been the bread-and-butter business model for installers like SolarCity. But homeowners, not the installer, get the 30% federal tax credit when they buy their systems outright. With installed costs steadily dropping, that became a more realistic option for more customers.

The most recent Tracking the Sun report from the Lawrence Berkeley National Laboratory says that the median installed price for a residential solar system was $4.10 per watt in 2015, less than half of what it was just seven years ago. At the same time, module efficiency has been increasing.

The report says that price declines since 2012 can be attributed mostly to lower “soft” costs plus reductions in the price of inverters and racking equipment. The cost of the modules themselves, which dropped steeply between 2009 and 2012, have since leveled off, the lab said.