Parking charges are linked to vehicle emissions. 

Croyden, for example, charges 90% less for zero emission vehicles, a vehicle emitting less than 185g/km CO2, is the discount 25%.
Hammersmith and Fulham charge £3 per hour instead of £5 if the CO2 emission stays under 75g/km. 
In the Netherlands allows an amendment to the Dutch Municipalities Act to lower parking rates for all electric and hydrogen powered cars.
And in Paris electric vehicles of residents can be parked for free for a duration of 6 hours everywhere in the city.

Picture source pixabay.