Of the 1.2 gigawatts of residential solar installed in the U.S. last year, 72 percent was third-party owned (TPO) in the form of leases and PPAs. The remainder was directly owned by the customer, much of it through loans. That’s according to the newest report from GTM Research, U.S. Residential Solar Financing 2015-2020.

FIGURE: Residential Third-Party Ownership Penetration and Installations by Ownership Type

Source: GTM Research U.S. Residential Solar Financing 2015-2020

The U.S. residential market segment has grown 15 of the last 16 quarters, and that’s largely due to financing solutions like leases. Since TPO took off a few years ago, the offerings have given customers across many demographics and socioeconomic categories the ability to afford a solar installation.

According to the report, three companies financed 56 percent of all U.S. residential solar installations in 2014. SolarCity led the nation with 34 percent, followed by Vivint Solar’s 12 percent and Sunrun’s 10 percent. Other leading finance providers included SunPower, NRG Home Solar, Sunnova and Clean Power Finance.

FIGURE: Leading U.S. Residential Solar Financiers, 2014

Source: GTM Research U.S. Residential Solar Financing 2015-2020.

Note: Market shares in this figure include each company’s 2014 financed systems (both TPO and direct) as a portion of all 2014 residential installed PV. The report also includes shares of the TPO market alone.

“The solar loan market has exploded,” said Senior Solar Analyst Nicole Litvak. “Every TPO financier has introduced or is planning to introduce a loan, and an entirely separate group of pure-play loan providers has emerged. Many of these new loans are structured such that they offer customers the same year-one savings as a lease or PPA.”

 GTM Research forecasts that by 2020, direct ownership will surpass third-party ownership in the U.S. residential solar market, accounting for 54 percent of the forecasted 5.2-gigawatt market.

The full report provides historical market shares for the top financiers, profiles leading finance providers, and details the market landscape. For more information, visit the report page here.