From Proterra’s web site:
Based in Golden, Colorado, Proterra manufactures the world’s first hybrid- and all-electric, all-composite body transit vehicles built from the ground up to offer dramatic improvements in fuel efficiency while generating ultra-low or no emissions. Proterra offers all-battery and battery dominant vehicles using an array of auxiliary power units, including bio-diesel, gasoline, compressed natural gas, and hydrogen fuel cells.
“Proterra’s mission is producing the world’s most energy efficient transit vehicles while offering the lowest lifetime cost of ownership,” said President Jeff Granato. “Our vehicles are the right choice for these times of skyrocketing fuel costs and economic uncertainty.