Mount Signal Solar, also known as Imperial Valley Solar Project, is a 794 MWp (614 MWAC) photovoltaic power station west of Calexico, California, United States, in the southern Imperial Valley, near the Mexican border. The facility was developed and constructed by 8minutenergy Renewables in three phases, with two completed as of 2018, and the third in 2020. It is one of the world's largest PV solar farms with a capacity of about 800 MWp (600 MWAC). The project has been supported by several environmental groups, as the power station was built on low-productivity farmland.