Denver adds 26-plug hub for 28 electric school buses

The buses have routes to run and a new place to recharge when they return. Denver Public Schools has installed 26 charging plugs at its Hilltop Bus Terminal, giving Colorado’s largest electric school bus fleet a total of 650 kilowatts of charging capacity before the district’s first day of school on August 24.

The hub serves 28 electric buses: 25 Blue Bird Vision buses recently added to the three already operating. Its 13 dual-port Kempower Satellite dispensers dynamically distribute available power across the plugs. Buses scheduled for longer routes can receive more energy, while those with lighter schedules receive less—a practical match for vehicles that return to the same depot and sit unused at predictable times. Winn-Marion led the electrical project, and PowerFlex manages the depot’s smart charging and energy use.

The financial case is promising but not settled. DPS says electricity should cost around $1,900 per bus each year, compared with $6,800 for diesel. Across the 25 new buses, the district projects annual fuel savings of about $123,000. The electric buses cost about $400,000 each, against $140,000 for a diesel bus, although grants and rebates covered the buses and charging infrastructure. DPS also expects around 75% less maintenance, because electric buses do not have engines, transmissions, or many other moving parts found in diesel buses.

Concretely, the new system gives DPS a way to measure whether those estimates hold up in daily service: the district plans to track electricity consumption, maintenance, and efficiency. It is also watching the largest uncertainty, the battery. Each battery costs $93,000 and carries an eight-year warranty; major repairs could begin around years nine or 10, roughly when diesel buses also start needing more expensive work. DPS says it does not yet have enough real-world data to compare lifetime costs.

The American Lung Association links diesel exhaust to asthma attacks, lung damage, and other serious health problems, with children especially vulnerable while their lungs are developing. The association says 26 million US children ride school buses, while 95% of the nation’s school buses still run on diesel. DPS has set a goal of cutting overall greenhouse gas emissions by at least 90% by 2050; transportation currently represents 14% of those emissions.