I don't think it is a viable option in reality. And if they do this it will only be on new cars so what about the older cars? How will they punish people that have the older cars? What will they require them to do to be in compliance?
Here'* a better plan:
Get 50 of the worlds best automotive engineers
Give them $1billion
Tell them to find a way to harness more than the, what, 10-15% of gasolines potential energy we use now.
Defying physics IS an option