With the flip of a switch, Las Vegas city officials today celebrated the powering up of 15,000 new solar panels that will provide energy to a nearby wastewater treatment plant.

The ground-mounted panels are packed tightly on 25 acres of city-owned land near Vegas Valley Drive and Nellis Boulevard.

The site had previously been a vacant strip of land the city used as a buffer for its wastewater treatment plant, which processes all of the city’s wastewater on its way to Lake Mead.

via lasvegassun.com