Updated Feb. 16, 2014

In 2014 solar adoption makes up a very small percent of the electrical generation mix in Arizona. But the trend is accelerating in favor of solar utilization not only in Arizona, but across the country.

What is the driver behind this growing trend? Most point to financial (business model) innovation. And one only needs to consider that it was not a technology innovation, rather a financial innovation, that fueled the automobile market in the U.S. in the 1910s, to understand why solar adoption rates are soaring.

The introduction of financing through GMAC finance took the American auto market from 7.7 percent adoption to 80 percent adoption in less than a decade.

A financial innovation unlocked the car market 100 years ago and is having a similar impact in the solar marketplace today. A new business model innovation (leasing) has fueled an increased adoption rate for solar electric which in turn is pushing costs down and further fueling the market.

In 2008, a company called SunEdison introduced a version of what is known today as the solar lease. Residential and commercial solar customers no longer need to invest capital in purchasing solar rooftop systems.

SunEdison offered to finance, install, own and maintain the solar panels on the rooftop of its customers. Homeowners did not have to take any risks. At the end of the (20-year) contract, the customer had a choice of purchasing the equipment at deep discounts or having them taken off the roof.

Soon after SunEdison, Solar City started offering a Solar Lease option and the solar market exploded. The concept caught on and other companies such as Sungevity and SunRun as well as local and regional companies joined the long list offering 'Solar Leases' or 'Solar PPAs'.

Partly as a result of these financial innovations, the solar market in America quadrupled from 2008 to 2012. Since 2012 the market has expanded even further as about 80 percent of all residential and commercial installations nationwide are now financed by third party-companies. In Arizona the number is closer to 90 percent.

But the economics of a lease versus out-right ownership is different in many ways. The lease is a contractual document that sells the property owner the solar output of the system. The 3rd party (system owner) in a lease maintains the RECs, and is the recipient of any rebate and tax incentive. A property owner that chooses to purchase their system outright receives all of the upfront incentives of a system but is also responsible for any maintenance of the system over its life.

There are a number of loan vehicles that a property owner may tap in order to purchase and own a solar system outright. These programs offered through lending institutions and government entities (i.e. property assessments) have been subject to considerable change. Please contact individual institutions to learn of any current financing options.