Communities across the United States are looking to replace their dirty diesel buses, ushering in what some analysts predict will be a boom in electric fleets. An electric bus sits under a charging station in Pomona, California U.S. November 16, 2017. REUTERS/Lucy Nicholson But transit agencies doing the buying are moving cautiously, an analysis by Reuters shows. Out of more than 65,000 public buses plying U.S. roads today, just 300 are electric. Among the challenges: EVs are expensive, have limited range and are unproven on a mass scale. A typical 40-foot electric bus costs around $750,000, compared with about $435,000 for a diesel bus. Cheaper fuel and maintenance expenses can lower the overall costs over the 12-year life of the vehicles. But those costs can widely depending on utility rates, terrain and weather. The technology is still a gamble for many cities at a time […]