A new solar installation is expected to save the City of Phoenix about $4 million in energy costs over the next 20 years.
According to bloomberg.com, the new panels at a water treatment plant should generate about 7.5 megawatts of power.
The almost 23,000 panels will provide about 70 percent of the water treatment plant's power, saving 15 million kilowatt- hours annually. Phoenix already uses a 5.4-megawatt SunPower solar array at Sky Harbor International Airport and smaller systems throughout the city.
Wells Fargo & Co. owns the new solar array.