Since moving to Florida in 2015, Brenda Probasco has been preparing for retirement strategically.She bought a three-bedroom fixer upper in Gulfport. Eliminated gasoline bills by buying a used electric Chevrolet Bolt. Stocked the house with energy efficient appliances. When it came time to replace her dilapidated roof, Probasco, 56, wanted solar panels but needed help finding an installer. She joined the St. Pete Solar Co-op in 2016, a then-fledgling effort led by The League of Women Voters Florida with FL SUN. The idea is for residents to band together and hire a single company to install systems on all of their homes, resulting in a 20 percent bulk discount and moral support to navigate a complicated process.With the 30 percent federal tax credit and co-op discount, Probasco used her savings to get 15 panels installed for $6,800 on the roof of her 1,264-square foot home.Her electric bill in August? $5.49."I've always been an environmentally conscious person, and I know climate change is real," said Probasco, a former real estate broker now working as a waitress. "I think we're getting to a point in Florida where when you do a checklist of things you need to have in your house like a refrigerator, solar panels are just going to be a part of that."As interest in solar energy grows in the state, more resident-driven co-ops are sprouting. FL SUN will launch co-ops in North Pinellas and Hillsborough counties Sept. 25, joining the dozen running across the state and others in formation.With the cost of building solar installations dropping 65 percent over the past five years and more cities looking toward clean energy, North Pinellas FL SUN Coordinator Dave Sillman said now is the time for both residential and commercial solar energy to boom. "We're trying to push it along to that tipping point, that's a key to the co-ops," Sillman said. Florida currently ranks 13th nationally for solar capability even though the Solar Energy Industries Association estimates the Sunshine State as having the third-highest potential for solar energy in the country.But the pace is picking up. The number of customer-owned solar energy systems increased nearly 40 percent in 2016, reaching 15,965 compared to 11,600 in 2015, according to the Florida Public Service Commission. That's still only a fraction of the state's 7.9 million utility customers — but it's progress, Sillman said."Not only is solar much more affordable now, if you can do it, it is the best investment you can make," Sillman said. "Solar systems in average pay for themselves in about eight and a half years and warranty for 25 years and should last 35 to 40 years, so they pay back two to three times what you invest in them," Sillman said. About 240 people joined the St. Pete solar co-op last year, and about 50 of those homeowners installed solar, according to St. Petersburg area League of Women Voters president Julie Kessel. Because there's no cost or join and no obligation to go through with installation, many of those residents participate in the co-op just to get information and learn about the industry, Kessel said. At co-op meetings, residents learn about the cost savings of solar, the environmental benefits and the logistics of installation. The co-op groups issue a competitive bid to installers and hire one together as a group.But another barrier to getting more panels on roofs is price. Although installation and capital costs are falling, a solar energy system can still push $10,000 depending on the size of the roof, out of reach for most families. Kessel said the league is working to bring alternative financing options to the area, like green banks to offer low and middle income families with good credit financing to buy panels. "The demand is there," Kessel said. "We know people call us all the time asking 'do you have the co-op up and 'when is the co-op coming back?' We are on the front lines for sea level rise in St. Pete and the surrounding beach communities. ... There are very practical reasons to adopt solar."Contact Tracey McManus at [email protected] or (727) 445-4151. Follow @TroMcManus.