The choice which person a self driving car has to kill will basically not occur in practice. But if we lived in a trolley problem universe, would you want to configure the killing prefs of your car yourself or should the government do it for you?
Conservation of energy might mean that you have to choose whom to give the excess energy to. I would think that about once a year, a driver may have to make such a decision. Too rare to warrant a special subroutine in a self driving car, but enabling the thought experiment.