One of the biggest greentech stories of 2013 has been the bullish sentiment on financing residential solar. The flood of financing (and consolidation) continues as more institutions clamor to invest in this new asset class. GTM Research sees the residential solar financing market in the U.S. growing from $1.3 billion in 2012 to $5.7 billion in 2016.

We've tried to keep up and log the steady drumbeat of announcements in this volatile sector.

One story has been the escalating rivalry between number-one solar financier/installer SolarCity and number-two solar financier/installer Vivint.

SolarCity versus Vivint

When SolarCity isn't poaching Vivint solar executives

, the firm is teaming up with Texas home builders such as CastleRock Communities and PSW Real Estate to offer solar as an option on new homes in 44 Texas communities. SolarCity has also provided a number of other innovative solar options. Last week, the firm announced a partnership with BMW to offer owners of the new BMW i auto access to its solar service option.

And in a major advance for the industry, the solar installer just completed the solar financing milestone of a solar securitization offering -- the first step toward securitization going mainstream. Solar securitization will help lower borrowing costs and provide a funding source for residential, commercial and utility-scale solar projects, resulting in billions of dollars of new potential financing for the solar industry.

On the Vivint side, the home security giant's solar group raised two more rounds totaling $540 million last month. The names of the investors were not disclosed. That's on top of the $200 million fund that was raised in the summer. 

“In less than three months, Vivint Solar has raised nearly three-quarters of a billion dollars to finance our solar projects,” Greg Butterfield of Vivint said in a statement. “These new financings will enable Vivint Solar to continue its unparalleled growth, while delivering simple, affordable solar solutions to our customers.”

The two companies are going head-to-head on raising money and putting those funds to good use.

Bank debt moving back into solar

OneRoof Energy is now offering both secured and unsecured loans for solar systems. OneRoof's new financial products include secured loans of up to twenty years and unsecured loans with terms of up to twelve years.

Canadian Solar just launched its Residential Financing Program in partnership with privately held Admirals Bank. Customers can borrow up to $40,000 for a residential solar installation, subject to credit approval.

The Digital Federal Credit Union

"may provide up to $100 million" in loans for its members (up to $50,000 per member) to finance solar projects with PV modules from SunPower. It's a novel customer acquisition strategy, with DCU acting as lead originator for a group of 36 credit unions formed to support SunPower's residential loan or lease programs.

More funds, more M&A

In August, SolarCity acquired its direct marketing partner, Paramount Solar, for $120 million. Last month, the solar installer and financier teamed up with Viridian, a retail energy services provider in the Northeast U.S. In October, SolarCity announced that it had acquired solar mounting hardware startup Zep Solar.

Solar Universe

added two new franchises in New York and New Jersey. The company acquired Gen110 in September.

Brightergy and Black & Veatch formed an alliance to develop $100 million in solar projects ranging from 25 kilowatts to 2 megawatts over the next three years, including commercial rooftops in Kansas City. Brightergy acts as the project developer and provides sales, marketing and financing resources. Black & Veatch provides engineering, procurement, construction and consulting.

Sunrun

and Nest have teamed up. As reported by GTM's Stephen Lacey, under the partnership, Sunrun customers can get a $250 Nest thermostat for free, along with another $250 credit for electricity; Nest customers interested in solar can get a $500 voucher for a Sunrun solar system.

Vivint Solar

 secured $200 million in two new tax equity funds to finance solar power systems on residential rooftops. Vivint Solar is the solar integrator and PPA financier unit within Vivint. Vivint is notable for its sales network and low cost of customer acquisition. The company was acquired by Blackstone for $2 billion in September of last year. Vivint Solar was the second-largest U.S. residential solar installer in the first half of 2013, according to the GTM Research U.S. PV Leaderboard.

In April, residential solar financing startup Clean Power Finance (CPF) announced the $37 million piece of a $60 million equity round that included Edison International, Duke Energy, Clear Sky, NextEra Energy's Investment arm, and Dominion. CPF has closed on an additional $20 million in equity capital from funds in the United Arab Emirates. CPF manages hundreds of millions in project finance funds for corporations and institutions.

SunPower's residential lease program has signed up a total of 18,400 customers and has about 147 megawatts booked to date, with $528 million in net aggregate payments. SunPower just raised $150 million in new residential lease financing.

Sungevity, the solar sales, financing, and software startup, won $125 million in new venture capital and project financing in January and landed another $15 million in funding, including investment from GE Ventures last month. Previous investment has come from Brightpath Capital Partners, home improvement store Lowe's, Vision Ridge Partners, Firelake Capital, Craton Equity Partners and Eastern Sun Capital Partners. SolarCity joined with Honda Motors on a $65 million residential solar project fund for the benefit of Honda and Acura car buyers earlier this year.

SolarCity also raised $500 million from Goldman Sachs in May.

OneRoof has raised more than $80 million in operating capital and finance capital from Hanwha, Black Coral Capital, U.S. Bank, The Quercus Trust, Yellowtree Energy and Spring Ventures.

In June, Sunrun announced three new funds totaling $630 million. Investors include JPMorgan and U.S. Bank. While U.S. Bancorp has been a big supporter of residential solar, this is the first entry for JPM Capital Corporation, a subsidiary of JPMorgan Chase & Co. Sunrun CEO Ed Fenster called it a "watershed moment."

SunEdison acquired EchoFirst, a solar, hot water, and air conditioning provider, along with a dedicated $50 million fund. SunEdison also announced that Wells Fargo is looking to invest more than $100 million of tax equity financing in 2013 and 2014 to fund solar DG projects developed by SunEdison in the U.S.

Shayle Kann, VP of Research at GTM, pulls it together here:

"The flurry of investment activity in the U.S. residential solar market reflects four trends which we have been focusing on recently at GTM Research. First, residential solar financing via leases and PPAs continues to be the dominant model today, with over a dozen companies now offering solutions in that space. Second, financing options are diversifying and debt is beginning to make a resurgence, as evidenced in part by SunPower's deal with the Digital Federal Credit Union. Third, retail electricity providers are increasingly viewing solar as a potential differentiator among their competitors, and we expect to see more partnerships like the SolarCity/Direct Energy deal over the next three months. And finally, customer acquisition is the new 'hot' space for residential solar innovation, and the M&A in that landscape is just beginning."

Source: GTM Research’s report U.S. Residential Solar PV Financing: The Vendor, Installer and Financier Landscape, 2013-2016

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