Late last year we broke the news that OneRoof Energy had raised a $50 million round A and project fund for opening up solar installation to the roofer trade and installing solar on a roof when it is being built or rebuilt.

It just makes sense that when you already have contractor boots on the roof that you consider financing and installing a solar system.

Today the company added $3 million to that total from venture investor Black Coral Capital to expand into new markets like Hawaii and Arizona with its "no-upfront-payment" solar lease. OneRoof Energy looks to close its second fund later in 2012.

Earlier investors in OneRoof include Hanwha International (the same firm with a controlling interest in Hanwha SolarOne), U.S. Bank (a subsidiary of U.S. Bancorp (NYSE:USB), The Quercus Trust, Yellowtree Energy, and Spring Ventures. U.S. Bancorp has provided financing resources for several other residential PPA firms.

Installing solar panels on residential rooftops is not an easy task. It requires specialized skills in design, electronics, and construction that have made this type of work the domain of a select and relatively expensive group of craftspeople.

Instead of relying on the few thousand specialized solar installers, what if you opened up that pool of contractors to the tens of thousands of roofers who are hungry for work in this economy and already have rooftop and construction skills?

OneRoof Energy works with roofers to lease and install residential photovoltaic systems. The firm builds and maintains the systems for homeowners and works with builders and roofers to integrate the roofing and solar installation into one streamlined process. As with most solar PPAs, there are no upfront costs, and monthly bills are roughly equal to or lower than current electric bills. A warranty covers the roof and the solar installation.

Mark Goldman of Armageddon Energy told us last year, "Starting now, you'll see roofers and other trade professionals like plumbers and electricians become the heart of the solar installation workforce. Now that module prices are economic, the only way to reduce the cost of solar is to cut sales and installation overhead. These guys have the tools and the skills to get the job done quickly and efficiently from one end of the country to the other."

This form of financing was largely nonexistent in solar a decade ago, but SunEdison pioneered the process for commercial installs and firms like SunRun, Sungevity, SolarCity and, more recently, Clean Power Finance and OneRoof Energy have joined the fray with their own slant on the finance tool for residential solar.

Third-party financing of solar, be it some form of lease or power purchase agreement (PPA), is becoming the leading method by which homeowners can afford to install solar. June of 2011 was the first month in which more Californians elected to go with a third-party-owned solar installation rather than a cash purchase, according to PV Solar Report.

This chart from GTM Research shows the growth of third-party financing in non-residential CSI deployments -- 17.6 megawatts in the first quarter of 2011, up from 7 megawatts in the previous quarter.


Here's some more data out through Q2 2011, again drawn from GTM Research's Solar Market Insight on residential third-party ownership in megawatts.


More data from GTM Research's Solar Market Insight, this on Xcel, the Colorado utility's third-party solar ownership share:



Recently, SolarCity told Greentech Media that 12,000 of their more than 15,000 solar projects completed or underway have chosen financing options. SolarCity's numbers are from across the U.S. and vary in size from residential to commercial.

OneRoof, if successful, would seem to give Hanwha SolarOne a new channel to the American residential market and provide a new addition to the small field of residential PPA firms, which include SolarCity, SunRun, Sungevity, and Clean Power Finance. Smaller players include Solar Universe, Ontility, SunPower, SolarCraft, Sun Edison, Centrosolar, and Suntech’s BriteLease program.



GTM's Solar Summit in Phoenix next month includes a panel on "Developing and Financing Residential PV." Go here for more details.