The conventional bus relies on diesel. This is smelly to handle and produces relatively high emissions. There’s a new competition between two bus companies to produce the perfect zero-emission vehicle. This is important because California which is the largest state, through its Air Resources Board has Zbus requirements. So far, only the Proterra Ecoride BE35 completely satisfies that requirement. This bus is manufactured in South Carolina and draws its components for assembly from thirty-three US states. This is an American bus and it has just broken a record in a trial. A bus traveled more than seven-hundred miles in twenty-four hours, simulating real-world conditions with an average speed of 29 mph. It performs in this way because the batteries can recharge in ten minutes. The competition is supplied by BYD e-Bus which easily manages the average of 155 miles for a day’s use in urban conditions — in a recent test, the BTD went more than two-hundred miles between charges. This is not, however, an American bus —it’s made in China — but it has locked up the Californian market. Proterra has recently sold into Massachusetts and Tennessee. It will be interesting which bus becomes dominant in this growing market.