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by liminal 776 days ago
I'd like to see a weight tax on vehicles. Lighter vehicles have less tire wear, so less pollution. They also require less energy to move, so less emissions. Plus lighter vehicles would improve pedestrian safety.
8 comments

Interesting idea. Apparently road damage goes up with the 4th power of the weight (https://en.wikipedia.org/wiki/Fourth_power_law)

Really trucks are probably not paying their fair share in that regard.

I wonder how it would be implemented in practice given how variable vehicle weights are depending on how they are being used. Weigh stations like they use for trucks?

It might also be a solution for gas taxes being insufficient to maintain roads as vehicles transition to electric. And in concert with the much higher weight of electric vehicles due to batteries still sucking at power density (maybe it would increase interest in things like aluminium-air)

Yes and so what makes the most sense is to make the tax increase with the 4th power of vehicle weight multiplied by the miles they travel. This way there are no perverse incentives. Everyone pays their fair share according to how much damage they cause.
I love pushing "Tire Taxes".

We all know that tires will emit rubber particles down to the point where the tire tred is 2/32th of an inch (from ~8/32ths of a fresh tire).

So just... tax the tires based on the ~6/32ths of an inch outer-diameter of the tire that turns into microplastic dust. Calculate the microplastic dust weight of the outer diameter + weight of tires and bam. You have a 1-to-1 correlation of tax to exactly the amount of particles emitted.

No weight^4th power required. The tire wear directly correlates to the pollution we care about. So tax / measure the tires directly, don't do anything else that's more indirect.

So you want to tax tires separately to whole cars? You don't think your scheme will induce perverse incentives as regards tread patterns, grip in different weather scenarios, etc.?

If I were a tire manufacturer I'd love this because I would:

* make tires that have not very much tread to wear through

* make the outer tread extremely hard so it wears (testably) much more slowly

* blame consumers for driving the tires wrong rather than make safe tires because we can hide behind T&Cs and our army of lawyers when accident rates inevitably increase

* put our fingers in all the tire installation and body shop pies to prpfit off of the new economic conditions that were created as a result of this tax

This feels like a permutation of run flat tires.

- Have half the life of regular tires

- Makes the outer tread extremely hard (and noisy)

- Consumers get the blame because they want safety (without the effort of a spare tire change)

- Increases the price

My State isn't very big.

If everyone started making tire taxes across the country, maybe that'd be a problem. But no one gives a care about just one small state making a tax like this.

Michelin isn't going to redesign their tires just to save $50 in tire taxes.

> * make tires that have not very much tread to wear through

That's not how physics works. You need deep tread to safely expel water and/or deep treads to make snow-impressions (if its a snow tire).

> That's not how physics works. You need deep tread to safely expel water and/or deep treads to make snow-impressions

Key word here is safely. A large portion of people would care more about saving $100 in tax than about the physics that makes their car less safe.

Doesn't account for road wear or pedestrian risk, though.
I have to imagine that if Car X wore out 5kg of rubber, that it would have had half the impact of another Car Y that wore out 10kg of rubber.

Right? Tire wear has to be directly correlated to road wear. They're in physical contact with each other after all, so it'd be as direct a measurement as any other possible methodology.

But rubber does not damage concrete, it's the weight of the vehicle that damages the concrete.

As an extreme example, if I floor a 2000lb Miata when the light turns green that will deposit a ton of rubber on the road. But that does nothing compared to just driving through the intersection in a 6000lb suburban.

Tying a tax to distance travelled requires accurate reporting of distance travelled. How is that not a perverse incentive?
We shouldn't care if you want to buy a 10,000 lb electric truck if you leave it parked in your driveway all year round. If we're not taxing based on distance then the perverse incentive is to drive big trucks until they fall to pieces.
Easy in places where it requires annual safety checks
which is really most anywhere these days, is it not? having lived in different states in different countries, this was always the case for me, but then again that's still a small sample size
US Federal Gasoline taxes haven't been raised since 1993; meanwhile US interstate systems and bridges are receiving C- rankings. This was the case before the Nissan Leaf or Tesla Model S, much less 5% adoption of new car sales being electric.

There is a ~$186B dollar annual shortfall in federal (road maintenance - excise tax revenues)

a civie engineer told me an overloaded 18 wheeler is about the same as 8,000 passenger vehicles making the same trip on the tar.
My canton in Switzerland uses this formula:

tax = k * P*0.9 / m*0.05

P: power in kW

m: weight in kg

k: currently 7.125

Minimizing tax means a small engine and a heavy car. (Though the tax difference between 1000 kg and 3000 kg is only 6%.) They also don't do subsidies for EVs, with the rationale that EVs affect road maintenance as much as other cars. Given that, the formula is backwards in terms of weight.

https://guide.autoscout24.ch/de/auto-unterhalt/verkehrsabgab...

It's penalizing high power to weight ratio, i.e. sports vehicles.
My local state is adding weight to our vehicle registration fees, but only slightly (ex: capping out at 5000lbs). There are vehicles as high as 8000+lbs commonly used, and I think those should have higher tax than the 5000lb class vehicles.
Having a cap makes absolutely no sense except politically. There’s not a diminishing impact here whatsoever.
There used to be only one weight tax (erm, registration fee). Now we have two weight classes, 3500lbs and 5000lbs.

Its an improvement, but why stop at two classes? Its nearly as bad as our previous law that was only at one weight class. Might as well follow the pattern at every 1500lbs up until no common vehicles are covered anymore. (6500lb and 8000lb are a natural extension of this new law).

Oh well, we can fix it in next year's debate, I guess?

This would be a good idea, because weight is the major factor in vehicle safety... if everyone else has a 6,000lb vehicle, you need one as well to be safe when they hit you. If vehicles on average got lighter, this would solve this problem. Unfortunately, EVs and modern crash tech have made cars much heavier. A 1970 small economy car like a VW Rabbit was ~1800lbs, that same car now (VW Golf) is now ~3200lbs.
> Lighter vehicles have less tire wear, so less pollution.

there are different tire rubber/synthetic formulations, as another independent (of weight) variable

I'm tired of viewing taxes as a punishment. Taxes are for funding the government. If you're going to tax someone make sure the money goes to something specific, like keeping tire junk out of waterways.

Some people like to drive, some people like big cars. Fix the tires, grand-daddy in all the existing cars, incentivize cleaner ones, and let everything age out.

They're doing it with heat pumps, why not cars?

A core economic concept is externalities, positive and negative. Positive externalities are undervalued by the market, negative ones are overvalued by the market, like cigarettes.

There aren't many ways to resolve externalities. If you pay people to quit cigarettes, people start smoking to get paid for quitting.

For negative externalities, sometimes you just really have to make the good more expensive, or we'll end up bearing the much larger societal costs down the road, like we did for lead in gasoline and widespread cigarette smoking.

It's not about punishment, its about pricing in externalities
On the level of the US federal government, taxes are absolutely not for funding. They could hardly be more removed from it.

They're a restriction the money supply, but they don't determine what funding is.

All taxes are behaviour disincentives. If we tax say income but not pollution, we're discouraging people from working while the price of pollution is not paid by the polluter. If we're subsidising clean cars at the same time, w'ere also having wage earners subsidise cars for the upper-middle class.

This is great if you enjoy polluting and not working, such as if you're a trust fund kid who likes to drive his big car everywhere while the poor and workers suffer the consequences, but is not a societally conducive state of affairs.

With cars, every incentive you can devise has reverse Robin Hood effects since the poor use transit and bicycles, and both incentives and disincentives are being used in practice anyways. It's in fact perfectly fair for people inflicting an unpriced externality on the broader population, through pollution, to pay a fraction of the cost of that externality themselves. If that disincentivizes the behaviour - is that so morally outrageous?

Is it truly fairer to instead bribe this wealthier than average group of polluters into not polluting through taxes on the rest of the population? If anything this creates a moral hazard insofar that it would seem the key to getting the government to subsidise your expenses is simply to pollute relentlessly and inflict costs on the rest of society and say "You can't just TAX us, you need to tax everybody else and pay us off!"

That would amount to a tax on (among other vehicles) electric vehicles, which weight a lot more than comparable ICE cars.
And rightfully so, IMO. Increased pollution from increased weight is a real issue.
Sure, but it doesn't seem politically viable to me.
Even more taxes on semi trucks that deliver the food that's already growing unaffordable that will be passed on to consumers then?
It's not hard to Fermi-estimate the impact on the price of a cabbage, say. What do you think it would be?
It could very easily just be on consumer vehicles, not commercial ones
Yes, buses too.