Source: SolarCity Corporation 

When it comes to energy, the political lines have been drawn. Democrats strive to support renewables and their subsidies, while Republicans root for energy independence with offshore drilling and natural gas. But rooftop solar may be a surprisingly bipartisan energy source.

Rising sun
Rooftop solar is soaring and, as any politician knows, an emerging trend is ripe for rhetoric. Although solar currently accounts for less than 1% of U.S. electricity generation, rooftop solar systems are gaining major ground.

More than 90,000 businesses and homeowners installed panels in 2012, 46% more than the previous year. Rooftop solar company SolarCity Corporation (NASDAQ:SCTY.DL) grew MW deployed by 109% from Q3 2012 to Q3 2013 and is expecting to celebrate its 1,000 MW of residential solar deployed this year as it grabs its strongest growth yet.

Source: SolarCity Corporation 

SunPower Corporation (NASDAQ:SPWR) has installed more than 100,000 residential systems globally since 1985. While SolarCity keeps its installation in-house, SunPower has scaled up by working with local dealers throughout the country, pushing it beyond SolarCity's 14-state stretch. Installing solar panel kits has never been easier, and the soaring stock prices of these two companies reflect a major boost in market confidence over the past five years.

SCTY Chart

SCTY data by YCharts  

Shady business?
Rooftop solar's biggest opponents point to simple economics. Solar power is not cost competitive with cheap natural gas or other sources, and its subsidies are skewing our national energy portfolio while sucking up taxpayer money.

While Democrats generally support renewable energy subsidies, some Republicans have voiced support for solar. For former Congressman Barry Goldwater Jr., it's a matter of choice. As co-chairman of Arizona-based organization TUSK (Tell Utilities Solar Won't Be Killed), Goldwater has pointed his partisan finger at the real elephant in the room: utilities.

As the second-largest solar market in the nation, Arizona has erupted as a regulatory battleground. Pinnacle West's (NYSE:PNW) Arizona Public Service Utility is fighting rooftop solar, lobbying government to remove subsidies, and push extra charges onto solar homeowners to cover grid-upkeep costs on its less-used system.

But Goldwater thinks monopolies are simply scared of change and he wants to ensure consumers can benefit from proper capitalist competition:

As a son of Arizona, I know we have no greater resource than the sun. Republicans want the freedom to make the best choice and the competition to drive down rates. That choice may mean they save money, and with solar that is the case. Solar companies have a track record of aggressively reducing costs in Arizona. We can't let solar energy --  and all its advantages and benefits it provides us -- be pushed aside by monopolies wanting to limit energy choice. That's not the conservative way and it's not the American way.

Tom Morrissey, fellow TUSK co-chairman and immediate past chairman of the Arizona Republican Party, compares energy choice to health-care choice and points directly to Pinnacle West's aversion tactics as stifling opportunity.

As conservatives, we are morally obligated to fight new tax proposals. Arizona Public Service's request to end net metering amounts to a tax on solar savings. It also seeks to line the pockets of a regulated monopoly through government intervention.

Will Republicans raise the roof?
Market distortions are a major no-no for most Republicans, but TUSK is admirably holding utilities to the same standards. The group helped to organize a 1,000-person protest in November to ensure Arizonian's rights to rooftop solar, and it will continue to voice its independent opinion in the years to come.

Ensuring a balanced energy market is in the best interests of all stakeholders, and the smartest companies will continue to embrace competitive change.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.