Proterra is an American automotive and energy storage company based in Burlingame, California. The company designs and manufactures electric transit buses and electric charging systems. Proterra's Catalyst series includes transit buses ranging from 35 feet to 40 feet in length and various battery configurations. Buses are charged through an overhead charging station that is placed at maintenance facilities as well as route terminals. Founded in 2004, it became a public company in June 2021 through a business transaction with a Nasdaq-listed special-purpose acquisition company.