The Board of Supervisors on Tuesday approved resolutions that give property owners in unincorporated areas access to clean-energy financing in the form of county loans paid back through property-tax bills. The property-assessed financing was developed in 2008 to make it easier to fund energy-efficiency, water-conservation and renewable-energy improvements to homes and commercial buildings. As Marin updates its climate action plan, increasing its 2006 goal to achieve a 30 percent reduction in greenhouse gas emissions compared to 1990 levels, state rebates for solar-panel installation have been fully expended and a 30-percent federal tax credit for clean-energy building is set to expire next year. County officials are banking on property-assessed clean-energy financing to offset the loss of rebates and push homeowners to help the county and state reach their reduction benchmarks, all while improving home values. “In order to maintain the momentum we’ve built over the years, and then to increase this [momentum] to meet our ambitious targets, we need to bring new financing tools online,” said Dana Armanino, a planner with the Community Development Agency.