At the moment there are tax incentives for EVs in many parts of the world. Already in Britain the tax take from fuel has dropped because of more fuel efficient cars and reduced mileage and this has left a 'hole' in the government's finances.
At some point EVs will be sold in big enough numbers to start effecting the tax income from fuel and the incentives will stop and some way will have to be devised to recoup the loss of 'road tax' from EVs.
Clearly electricity cannot have a road tax portion nor can road tax be sourced centrally so??
Tolling by miles driven would seem fair but then cars would have be arbitrarily divided into EVs; RE-EVs; Hybrids; Plug-Ins and pure ICE-age cars - what a contentious mess that would be!
If all cars were tolled on mileage, then fuel tax would have to be dropped from fuel prices - and in many countries this would cause a huge drop in price thus undermining some of the running cost advantages of EVs.
This could ironically encourage a swing back to ICE-age cars unless there were other 'disincentives' such as ICE cars being banned from city streets as unsavoury and polluting.
Controlling and monitoring road use for tax purposes in a reliable and fair manner (visitors from other countries? - prevalent in Europe unless a central road tax was applied..)would be a hugely complex exercise and contrary to civil liberties in some people's minds.
How do others see this developing?!