WASHINGTON - Energy Secretary Samuel Bodman has inaugurated one of the largest solar power systems in the nation’s capital, installed atop the U.S. Department of Energy’s (DOE’s) Forrestal Building. At a rooftop ceremony, Bodman energized the system for the first time. The solar electric photovoltaic (PV) system will generate approximately 200 megawatt hours of electricity annually, provide up to 8 percent of the Forrestal complex’s energy during peak hours, and save as much as $26,000 in utility costs in its first year of operation.
“The significance of this solar array is both practical and symbolic - it improves the way the Department consumes energy and it is a symbol of America’s commitment to using the best available new technologies to confront the energy challenges we face today and will face tomorrow,” said Bodman.
The photovoltaic system is approximately 40-50 times larger than a typical residential system. The system is integrated into the current roof and is not visible from points below the roofline. SunPower Corp., a Silicon Valley-based manufacturer, designed and installed the system, which is comprised of 891 individual photovoltaic modules, each with an efficiency of 18.5 percent, among the highest efficiency modules available for purchase today. Insulation incorporated into each module has the potential to provide additional energy savings of up to 30 percent by reducing the building’s heating and cooling load.
DOE worked closely with the General Services Administration (GSA), the federal government’s acquisition agency, to purchase and install the PV system. Additionally, the system will help DOE avoid annually the emission of up to 186 metric tons per year of greenhouse gases.
While generating clean, renewable, and emission-free electricity directly from the sun, the solar installation will also serve as a learning demonstration project for the public and other federal agencies. A large video display, installed in the public area of the DOE lobby, monitors electricity generated by the solar array and explains other aspects of the project. The rooftop installation also includes a technology showcase area for monitoring and evaluation of current and cutting-edge solar energy technologies.