The secondary costs of running a diesel fleet are also huge! Diesel motors generate a substantial amount of fine particulate that is unhealthy for anybody, and particularly unhealthy for children.
Even if an electric fleet is the same cost, changing over would save tons of money and alleviate tons of suffering. It's the right thing to do for any ethical reason you can consider.
Unless, I suppose, you're intent on making the poor suffer. Diesel buses are very cost-effective at accomplishing that.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC121970/
Even if an electric fleet is the same cost, changing over would save tons of money and alleviate tons of suffering. It's the right thing to do for any ethical reason you can consider.
Unless, I suppose, you're intent on making the poor suffer. Diesel buses are very cost-effective at accomplishing that.