Solar-Energy System Tops Transit Divisions With Savings
Hailed as the largest solar-power installation of its kind in the transit industry, Metro Bus divisions in Sun Valley and Chatsworth, CA, recently received a renewable-energy makeover that is reducing air pollution as well as electricity costs. The project included the installation of ASE 300 solar modules and companion mounting systems from Schott Solar, Inc., based in Roseville, CA. In all, the photovoltaic modules cover more than 43,000 sq. ft. of rooftop area that crowns Metro’s Maintenance and Transportation buildings at each bus division. The facilities were also outfitted with 1,648 solar panels, which offer enough generating capacity to power more than 100 homes a year for 25 yrs. To harness solar energy for cost savings, multiple inverters convert d.c. power generated by the solar modules into a.c. power, which is then directed back into an electric utility grid. In turn, a reverse meter deducts the amount of electricity generated by the solar panels from each bus division’s electric bill. Since the project was implemented, approximately 1 yr. ago, the solar-energy system has saved Metro Bus divisions at least $185,000 in electricity costs. Overall, the system produces 425 kW. a.c. of clean, renewable electricity—enough to provide up to 20 percent of each bus division’s total energy requirements. By using the solar-energy system, emissions savings from avoided fossil-fuel generation is equivalent to removing more than 500,000 lbs. of carbon dioxide, 1,000 lbs. of nitrogen oxide, and 2,500 lbs. of sulfur dioxide per yr.—similar to taking 100 conventional cars off the road. Total cost of the solar project was $3.3 million, more than half of which was paid for by rebates or incentive programs provided by the area’s utility companies. Metro Bus plans to recoup its own $1.48 million investment within 7 to 10 yrs., through reduced electricity costs. The solar-energy system is designed to last 25 to 30 yrs. Schott Solar, Inc., Roseville, CA