Five rooftop solar energy systems worth 2.4 megawatts have been installed by the US military, as part of base improvements at the US Navy base at Pearl Harbor now know as Joint Base Pearl Harbor-Hickham. The project cost $15 million and was funded under the American Recovery and Reinvestment Act.
The installation uses solar panels from SolarWorld, produced in their Californian and Oregon facilities. The solar panels have been installed but final configuration will be completed in the coming months.
More than 2,000 photovoltaic panels have been fixed to the roof of one of the city state's main buildings, enabling the Holy See to cut its carbon dioxide emissions by about 225 tonnes a year, saving the equivalent of 80 tonnes of oil annually. Looming over them is the imposing bulk of St Peter's Basilica, but the panels will not be visible from ground level, leaving the Vatican's impressive skyline unblemished.
The solar energy system covers the massive roof of the "Nervi Hall", where Pope Benedict XVI holds general audiences. The 2,400 panels, designed by a Germany company, will heat, light and cool the hall and several surrounding buildings, producing 300 kilowatt hours (MWh) of clean energy a year.