On Wednesday, Proterra Inc, a provider of clean commercial transit solutions including zero emission city buses, announced $20 million in funding from cleantech investor, MK Energy and Infrastructure LLC (MK E+I). The money will fund Proterra’s efforts to provide cleaner and more economical public transportation options to transit agencies in the U.S. and internationally.

MK E+I’s investment will accelerate the construction of Proterra’s first full-scale manufacturing plant in Greenville, S.C., which will break ground later this year and have capacity to make 2,500 EcoRide BE-35 buses annually and employ 1,300 workers over the next five years. Funds will also be used to advance Proterra’s clean technology research and to promote policies in support of clean commuting.

At the Greenville plant, Proterra will manufacture its transit bus, the EcoRide BE-35, a patented, zero emission, fast-charge, battery-electric transit bus that replaces traditional diesel buses. The EcoRide BE-35 achieves 500 percent greater fuel efficiency than conventional diesel buses and more than 400 percent greater efficiency than the most advanced hybrid transit buses traveling the roads today, according to the Federal Transit Administration sponsored Altoona, Penn. Bus Testing Center.