Retired Episcopal Bishop Bud Cederholm — affectionately known as the “Green Bishop” — sprinkled holy water on the new solar panels installed at Grace Episcopal Church on High Street. Cederholm, who earned his nickname for his environmental advocacy, got a lift in a city truck to sprinkle water on the 25-kilowatt solar installation. Grace Episcopal is part of The Genesis Covenant, a worldwide coalition of Christian churches that aim to save the environment. Each member commits to reducing its own carbon footprint by 50 percent. Along with solar panels, Grace Episcopal has installed compact fluorescent lights, energy-efficient appliances, and a high-efficiency gas heating system.