Solar energy was once an obscure utility that only people with money and hippies cared about. (Rich hippies were too busy having an identity crisis to have an opinion.) The Solar Electric Power Association's explosive growth in the last decade is proof the sun has become more mainstream.

Julia Hamm is the woman behind SEPA’s growth from a one-person shop with a $300k budget 10 years ago to a 25-person organization with a $6M budget. It represents over 900 member companies from traditional utilities and solar. The industry has seen 49% growth in the use of solar as a utility in the last year, along with a rise in solar power plants and distributed rooftop solar generation. And SEPA’s annual trade show, created by Julia in 2004 and taking place this week in Las Vegas, draws 15,000 people.

Julia, who’s lived in a solar-powered house since 2008, says it's catching on because the cost for consumers has dropped 64% since 2010. They have the choice of buying solar with low-cost loans or leasing systems from solar providers. She’s also seeing community or shared solar sites. Only 25% of roofs in the country are eligible for panels, based on sun positioning and whether consumers rent or own their homes. Consumers can own a portion of a community system and get a credit on their energy bill.

Much of SEPA's revenue was coming from its annual trade show and the organization wanted to diversify. It started seeing increased demand for business advisory services and would refer member companies to private firms. But two years ago the organization, seen here on a recent retreat, started offering consulting to members, creating another revenue stream. As for challenges ahead? Julia tells us utility regulations need to change as the power grid becomes more decentralized. And SEPA, as an organization, has to move quickly to remain relevant to the industry.