Real-world depot charging and battery life for electric buses

[KevinWS]

I work in the procurement department for a mid-sized city's public transit authority, and we're in the early planning stages of transitioning a portion of our aging diesel fleet to electric buses. While the environmental benefits are clear, I'm tasked with building a realistic long-term financial and operational analysis, and I'm seeking insights beyond manufacturer brochures. For transit agencies or municipalities that have already integrated electric buses, what have been the most significant unexpected challenges and costs in daily operations? I'm particularly interested in real-world data on electricity demand for depot charging, the actual lifespan and degradation rate of batteries in heavy-duty cycling, and the maintenance cost comparison for drivetrain components versus traditional diesel engines over a 10-year horizon.