As 2012 comes to a close, Sunrun principals predict next year will be the busiest one yet for residential solar adoption.

Susan Wise, Sunrun spokeswoman, said solar and green energy will likely transcend politics as adoption continues to grow most dramatically among the middle class and the third-party solar service model becomes increasingly popular. Those three trends are likely to be driving forces in solar industry growth in 2013, she said.

Despite a rocky election year when energy seemed like a thoroughly divisive topic with republicans championing fossil fuels, everyday life in America is much less divisive.

“People are making green lifestyle changes regardless of their political beliefs,” she said. “In fact, republicans are more likely to make green home improvements than democrats.”

Sunrun conducted a survey and found that homeowners who voted for Mitt Romney were more likely to have made green home improvements than those who voted for Barack Obama in the 2012 election. About 64 percent of Romney voters to 58 percent of Obama supporters said they greened their homes in the last five years.

“We believe the reason is that green isn’t just an environmental choice anymore,” Wise said. “It’s a smart financial choice, too.”

The study, which Sunrun commissioned and Harris Interactive conducted, found that while only 33 percent of Romney voters believe in global warming or global climate change, 87 percent said they would be motivated to make eco-friendly lifestyle changes if it saved them money.

And Wise said solar is increasingly becoming a cost-saving option.

Homeowners who have the money to buy their systems outright upfront, might be able to avoid paying an electric bill ever again. And rooftop solar sales are on the rise nationally.

But the biggest growth market for solar is in the middle class, where most people will not be able to afford buying solar installations outright. That’s where third-party solar service providers like Sunrun come in. The model allows homeowners to have a company like Sunrun install panels on their roof with no upfront cost. They contract to buy power from the solar company, usually at a discounted rate, for 20 or 25 years.

As a result of the new model, Wise said solar adoption among California's middle-income markets has increased 445 percent since 2007. “More and more people are realizing that they have a choice,” Wise said.