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by buro9 861 days ago
Weight is the best way to tax vehicles.

It correlates to the amount of energy needed to move it, generally with the size of the vehicle, and highly with the particulate pollution from brakes and tyres (yes I'm aware of regenerative braking), as well as the amount of wear and tear on the roads and infrastructure, etc.

European cities were never built for large vehicles, we should be going towards smaller vehicles, a Fiat 500 EV would be well within the limits described (at only 980 kg) even without the extra weight allowed by EVs.

Even if one argues an EV is good for the environment... they could still be better for the environment by being smaller and weighing less as it would take less energy to move them.

But looking at things like the Mercedes EQS SUV (3,375 kg), I drove behind one of these at the weekend and it is huge, it was scary seeing it pass a cyclist on a narrow London street. Living in a dense capital city, I would love if London followed suit here.

3 comments

Not only the energy though. "Tire emissions" are a serious problem and it's competing with ICE emissions. EV's are considerably heavier so they produce lots of fine particles from the tires. Maybe in the North America they're not that important since other cars are as heavy (SUVs and Trucks). But in Europe, EV's are by far the heaviest of the regular use vehicles.
While I agree entirely I just wanna correct you for a bit:

The Gross Vehicle Weight (GVWR)refers to the maximum weight a vehicle is designed to carry including the net weight of the vehicle with accessories, plus the weight of passengers, fuel, and cargo, which is indeed a hefty 3375 kg.

The Weight Unladen (EU) is still a ridiculous 2810 kg for the EQS SUV 580 4matic

Wait, what? A 3-tonne vehicle that can only carry a measly 500kg of cargo, including the driver and passengers? Who approved that idea, and how come they still have their job?
thanks, I did wonder if I was making a fair comparison

I won't edit, as your correction is clear and the context would remain

> Weight is the best way to tax vehicles.

No it isn't. Even the most simple look into EV database would have shown that this is flat out wrong. There are heavy and big vehicles in there using very little energy and small ones using a lot.

So what should be taxed is the actual efficiency - either per individual vehicle which would also incentivise reasonable driving (could be easily done by either submitting two numbers, similar to what is already submitted to insurance) - or by using the test ratings which is a good approximation.

It's quite tricky actually.

There's other negative externalities from car usage apart from the energy usage, like tire and brake dust, congestion, accidents, and road wear. And using up limited space in cities for parking. Etc. etc.

Even if you only wanted to tax energy usage, that clearly correlated with the amount of fuel or electricity used. Taxing liquid fuel is common and a sensible choice, however you can't slap on a big tax on electricity in general since if anything we want to encourage electricity use in favor of fossil fuels (e.g. heat pumps powered by zero-carbon electricity instead of gas heating, or indeed EV's instead of ICE vehicles). And arguably for electricity, it would be better by slapping a CO2 tax on the producers (or some roughly equivalent scheme like cap-and-trade) rather than taxing electricity generally.

And of course, if you want to tax by miles driven, that then gets into all kinds of problems how to track that in a way that doesn't enroach on people's privacy. Say, checking the odometer during yearly inspections?

So where does that leave taxing EV's? Maybe a flat yearly fee based on the weight isn't that terrible, and it's at least cheap to administer and doesn't leave much space for cheating. Although that is of course very unfair to those who live out in the boonies where parking space is not at a premium and drive very little.

You can slap a tax on the car. You simply take energy used/miles driven and that's your multiplier for a yearly vehicle tax. It could be collected by insurance companies (that usually require you to submit the miles driven anyway) on behalf of the government .

As for the other things, such as congestion, I believe it when I see proof that there is a big difference between cars. Even if there is, the priority right now should be energy efficiency, because reducing CO2 emissions is fairly urgent.

I fully agree reducing CO2 emissions should have a high priority. Which for fossil fuels would mean a quite substantial tax on the fuel volume, but for EV's it's trickier since electricity is used for many other things, and electricity production is already taxed for CO2 emissions (or cap and trade etc). There's no particular reason, from an emissions perspective at least, why electricity for EV's should be taxed higher than, say, for domestic use. If anything, an extra tax on electricity could be counter-productive if it causes more people to prefer ICE cars.

Which implies that a vehicle tax should then be primarily concerned with non energy use types of externalities. And maybe generally funding road construction, and so on. Probably a lot of that is more accurate if the tax is a function of distance driven than a fixed cost, true, assuming you can reliably get that information in a privacy compatible way.

No why should you ignore road deterioration? Road deterioration is Weight^4