The cost of buying a new car could go up by €1,000.
An overhaul of the Vehicle Registration Tax (VRT) is being proposed ahead of October's budget.
The Irish Independent reports the government's Tax Strategy Group wants buyers of new cars with 'average' or 'above average' emissions to pay more tax - to encourage greener vehicles.
Science Journalist Sean Duke says the government should be offering more incentives to buy electric cars:
"I think it's quite likely given that the Greens are there", says Sean.
"Really, the situation with e-cars has gone on for a while now and we're not making inroads.
"What they need to do as well as this is this 'push item', which is a very brutal thing, is to offer better 'carrot incentives' if you like."