Commercial solar systems are mainly rooftop mounted but some systems are mounted as ground systems and can also feed electricity into the local distributed grid but often use it on site either in net metered or behind-the-meter applications. Commercial facilities can be a great way to use unused space on the roof of a shopping mall, factory, storage facility or unused land next to a farm. They could earn money through a PPA, or simply supplement the site’s power demand, and in some cases, they can be set up to provide backup power in case of grid failure.