On another point , when lots of us some time in the future are driving around in electric or hydrogen powered cars where is the govt going to get all the tax from as half of the price of petrol/diesel is tax !
Road pricing. You'll be charged by the mile, pollution/traffic density, and time of day. Peak time journeys on main routes will cost more than rural journeys at quiet times. Roadside traffic sensors will check for the necessary transponders in cars and send out fines for cars that don't have them.
