The combustion engine has been handed a lifeline. The European law demanding all new cars sold from 2035 produce no emissions, effectively killing off ICE cars, has been modified to provide an exemption for cars running on synthetic fuels.

Cars running on these e-fuels still produce tailpipe emissions, but the fuel is considered climate carbon neutral because carbon is consumed in the production process. The exemption means the likes of BMW, Porsche, Ferrari and Lamborghini will all be able to sell traditional high performance ICE vehicles in Europe to those willing to pay handsomely for the privilege.

E-fuels are currently produced on such small scale that that a gallon costs around $189 (£44 / €50 per liter) just to produce, never mind sell, according to the Potsdam Institute for Climate Impact Research. That makes it around 100 times more expensive than petrol, and even if the cost falls to below $1 per liter to produce once large-scale production is underway, it’s still likely to cost considerably more than conventional gasoline at the pump. No wonder Iveco boss, Gerrit Marx, recently likened e-fuels to champagne for cars.

Your average millionaire Lamborghini owner might not balk at the thought of spending a few hundred dollars to get his rocks off in his 2035 V12 Lambo on a Saturday afternoon because he can afford it and the money he’s tipping into the tank is buying an incredible experience that an electric alternative can’t match. But what about the person who buys a used ICE-powered BMW M car a few years after 2035?

Related: Stellantis Is Readying Its Engines To Run On Synthetic Fuels

 QOTD: How Much Would You Pay For A Gallon Of E-Fuel?

To stop people with post-2035 ICE cars filling up on cheaper traditional gas the renegade combustion cars are going to have to be fitted with some kind of special filler neck that can only accommodate an equally special fuel pump nozzle, or have some kind of ECU code that detects a money-saving cheat attempt in progress and won’t let the car run. But if you’re buying a used M car, the chance are you’re not as rich as new-Lambo dude, so you can’t simply throw a ton of money into every fill.

So taking today’s gas price wherever you live as a starting point, how much more would you be willing to pay for a gallon of e-fuel to drive a combustion car? Thirty percent more? Fifty percent? One hundred?

We should make clear that this European ruling doesn’t change anything happening in North America, where California has also committed to banning sales of new cars that produce tailpipe emissions, and other states are certain to follow its lead. But it’s not beyond the realms of possibility that e-fuels could also get an exemption in North America, so you guys can play along, too.

Drop a comment below and let us know what kind of markup, if any, you’d be willing to stomach on a gallon of e-fuel.

 QOTD: How Much Would You Pay For A Gallon Of E-Fuel?