A pilot project in Austin, Texas, designed to test integration of large rooftop solar with the utility’s grid came to fruition this week with the unveiling of St. David’s Episcopal Church’s 146-KW solar array.
Church members had the idea to put solar panels on the parking garage a decade ago, but the plan came together last year when low interest rates and improved technology were combined with government rebates.
The cost of solar panels has dropped 80 percent since 2008, including 20 percent in 2012 alone. And Austin Energy offers creative financing that pays customers a “value of solar tariff,” which is calculated based on expected fuel savings, offset power plant construction, transmission and distribution savings and environmental benefits.
AE calculates that value to be 14 cents per kWh paid to those generating solar power.
St. David’s will be paid a solar tariff for all the solar electricity its system produces over its lifetime, diverting over $500,000 that would have been spent on energy to programs like the church’s homeless shelter.
Another barrier crossed was the design of AE’s downtown distribution system. Previously, rooftop solar was limited 20 kW but project developer Meridian Solar was able to engineer and calibrate the AC-DC inverters connecting the solar panels to the grid so that the system produces the maximum amount of energy without disruption.
This collaboration unlocked the financing and technical know-how required to install 146 kW of solar energy on an already crowded downtown grid, thereby reducing the church’s bill and providing Austin Energy with a source of clean energy located at the center of its electricity demand hub in downtown Austin.