A 120-year-old oak tree stands on the south side of our house, towering over most of the roof below. Not ideal for photovoltaics (PV), needless to say. But we still went almost all the way solar.
How’d we do it? The solution is called “community solar”, where a local solar facility is shared by multiple community subscribers who receive credit on their electricity bills for their share of the power produced. In our area, community solar is offered by Neighborhood Sun, a Maryland based solar energy corporation. We put no money down to sign up. Neighborhood Sun secured investor funding to acquire an old construction landfill and install the PV solar arrays. The project produces 5 megawatts of energy that is delivered to customers by Pepco, our local electric utility company. Every month, Neighborhood Sun charges us 5 percent less for our electricity than we were paying for the electricity provided by Pepco, which derives over 90 percent of its fuel mix from coal, natural gas, nuclear and oil. We pay Neighborhood Sun to produce nearly all of our electric power and pay Pepco only for our power distribution costs and a small amount of power generation. Our goal is to buy 100 percent solar as future projects come online.
Efficiency first. Then solar.
Before considering the solar option, we had a BPI GoldStar Contractor conduct a home energy audit and do extensive air sealing and insulation work to reduce our home’s energy consumption. We changed all lights to LEDs and installed a mini-split heat pump. It just makes sense to reduce the load before buying energy for your home.
Placement of community solar projects
Locations that don’t consume valuable farmland, such as landfills, make ideal locations for community solar projects. The photos above demonstrate how community solar can work in rural or urban areas on land that is not prime for development or farming. Germany has an extensive network of PV arrays along the famous “Autobahn” highway system. There is even an emerging technology for embedding PV systems beneath highway surfaces.
Even though Germany is far from being a sun-drenched country, it has one of the highest solar power outputs in the world and boasts cutting-edge research and many new industry actors. Over 1.64 million solar arrays have been installed with a capacity of 43 Gigawatts. Germany estimates that it will expand to 96 Gigawatts of production by 2030.
In the solar expressway project shown on the left, the road surface is made of a transparent, weight-bearing material that allows sunlight to penetrate. The panels, covering 5,875 square meters, can generate 1 million kWh of power in a year, enough to meet the everyday demand of around 800 households.
In summary, community solar allowed us to subscribe to a solar project and enjoy the benefits of virtual net metering, which is like having solar on your roof without having to install any panels or make any upfront payments. And, we pay 5 percent less for our clean electricity than we were paying for our carbon-based electricity.