Grayslake, IL. Grayslake Community High School District has announced the construction of two rooftop solar photovoltaic (PV) systems as well as a ground mount system, making it one of the first public school districts in the state to adopt PV on a large scale. The declining installed cost of solar has made this cost effective for the District and will result in an estimated net savings of $9.8 million over 25 years. Both Grayslake Central HS and Grayslake North HS will have roof-mounted solar arrays with an additional ground installation at North HS. Construction commenced on November 15th. At completion, a total of 2.9 megawatts (MW) will be produced and offset an estimated 32% of utility costs.