This photograph features the 132-panel rooftop photovoltaic (PV) system installed by the Milwaukee Public Library. The array was installed during an upgrade to the 120-year-old building’s roof. The system is expected to produce 40,000 kilowatt hours per year, nearly 10% of the library’s electricity needs. The library’s newly-installed green roof also includes a garden of hardy perennial plants. The plants, which include two varieties of a flowering species called sedum, Karl Foerster Feather Reed grass, and chives, were selected for their abilities to absorb rainwater and withstand the variable Wisconsin climate. The roof garden will help control runoff, remove pollutants, and regulate the building’s temperature. Users of the library’s Web site can view a Fat Spaniel system monitoring the amount of electricity being produced by the solar array.