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I am working on research towards the goal of introducing strict federal weight penalties for consumer vehicles. Cars are simply massively overbuilt for their a

• ajross 3y ago
  Naively that's going to end up disproportionately penalizing EVs[1], which sounds exactly backwards to me. "Weight" is not the correct factor to optimize, basically. [1] Which are heavy, because they can't source 2/3 of their reaction mass from the atmosphere and have to keep all the reactants in the battery at all time.
  • troutwine 3y ago
    > "Weight" is not the correct factor to optimize, basically. Is it not? Particular matter from tires is a major factor in air pollution and the heavier the vehicle the more that ramps up.
    • ajross 3y ago
      Absent numbers, I'm gonna go with "Mass-dependent increase in tire-derived particular air pollution" isn't the right factor to optimize either.
      • calvinmorrison 3y ago
        Its not just tire pollution but road wear
      • troutwine 3y ago
        Alright? It's not clear by implication what you actually do want to optimize for but the weight/particulate problem is a fairly well-known problem. For instance, from the California Air Resources Board: https://ww2.arb.ca.gov/resources/documents/brake-tire-wear-emissions https://ww2.arb.ca.gov/resources/documents/brake-tire-wear-e... It's something the tire industry has been fretting over for a while: https://www.tiretechnologyinternational.com/news/regulations/pollution-from-tire-wear-1000-times-worse-than-exhaust-emissions.html https://www.tiretechnologyinternational.com/news/regulations...
    • deleted 3y ago
      [deleted]
  • quadrifoliate 3y ago
    It should incentivize manufacturers to build a lot more Nissan Leafs (111 MPGe) and a lot fewer F-150 Lightnings (68 MPGe).
    • ortusdux 3y ago
      I agree. For reference: -Nissan leaf - 3500 to 3900 lbs -Tesla model 3 long range - 4250 lbs (131mpge) -F150 lightning - 6000 to 6900 lbs
  • hannob 3y ago
    For safety, weight is not the only, but a very relevant factor to optimize for.
  • ambicapter 3y ago
    What is the correct factor then?
    • ajross 3y ago
      Fuel consumption? Net total particulate emissions? Net involved fatalities (regardless of fault)? It's not like this is hard. Those are the things people care about reducing. At best, vehicle mass is a proxy measurement for those things. But the thing is, you use a proxy measurement when the things you're trying to measure are hard to measure. That stuff is easy! Fundamentally my point is libertarian: If we want to regulate safety, we should regulate safety and not play dumb games with weight rules that then need to be tuned for EVs or whatnot. Fine-tuned rulemaking doesn't work.
  • bryanmgreen 3y ago
    Correct - a "one-size fits all" solution would be foolish! But... This has been accounted for to not penalize EVs disproportionately :) Hopefully battery tech can improve at a steady pace that there are in the near-ish future notable reductions in weight.
  • zip1234 3y ago
    Weight should certainly be part of the calculation. Road wear, momentum at speed, and particulate emissions (including from tires) all increase with weight.
• quadrifoliate 3y ago
  Building upon this, the light truck loophole [1] means that there is currently a sort of arms race ongoing if you are concerned about car safety. Car manufacturers are happy to build the majority of their consumer-facing vehicles as "light trucks" so they can ignore environmental standards, and those of us that want smaller, lighter, and more fuel efficient vehicle need to compromise on safety. SUVs need to be heavily penalized, and need to have far stricter licensing requirements. This will bring down emissions much more than some blanket move to EVs, and be beneficial for safety as well. On the surface, weight penalties seem to be an effective way to accomplish this; I am curious if there are any examples or case studies about this that you can cite, 'bryanmgreen. ---------------------------------------- [1] https://jalopnik.com/every-car-looks-like-this-thanks-to-a-gigantic-regulato-1849837803 https://jalopnik.com/every-car-looks-like-this-thanks-to-a-g...
  • Sevii 3y ago
    The regulations need to be changed, it makes no sense that you can’t buy small pickups in the us like the Toyota hilux.
    • vel0city 3y ago
      The current generations of Hilux and Tacoma are extremely comparable. Its not like the Hilux is really that much smaller. A couple inches here, a couple inches there, and roughly the same weight.
      • Sevii 3y ago
        Well, I wish they sold a smaller one like the ford maverick or classic import hiluxes.
        • samsolomon 3y ago
          I’d really love a hybrid maverick, but they are impossible to get. People are still waiting on their 2021 Maverick orders. I do think the popularity of the truck has sparked something in the auto industry. I believe Toyota is working on a competitor, but we likely won’t see that for another year out two.
• autokad 3y ago
  > Cars are simply massively overbuilt for their average use case. Reducing weight of vehicles is a very achievable goal that will cut emissions dramatically while also having additional benefits like global supply chain material and emission reduction, pedestrian safety, and road maintenance. Please don't. we don't need more idiots telling us how to live our lives and micro managing us on how you feel we should live.
  • TheCoelacanth 3y ago
    Yes. I don't care how many pedestrians need to die. Just don't take away my freedom to drive to the grocery store in a vehicle larger than a WWII tank.
    • biomcgary 3y ago
      Part of the reason why the United States had both a Senate and a House is to make sure that more rural states had adequate representation of their interests, which differ substantially from urban areas. Rural areas don't have pedestrians because the distances are too big. Cities and heavily urban states could fix their pedestrian safety problems easily by creating massive local registration taxes on large vehicles, without a federal tax penalizing rural areas. The distance I travel to get groceries would be a net waste (financial, environmental, etc) if I had to make multiple trips rather than packing two weeks of food in one trip. More broadly, I really wish activists / reformers (of any stripe) would recognize the limits of their own knowledge and experience and realize that the world has more diversity than dreamed of in their philosophy.
      • TheCoelacanth 3y ago
        Are you feeding an army? I can't even imagine buying enough food at one time to even fill a small sedan
        • hdhuegau6hfhd 3y ago
          Fill is an interesting verb. I suppose you could try to tetris it up each trip to the store, but unpacking would just as inconvenient as packing. That said, if you buy a weeksworth of food for 3 kids, sedan may easily overflow.
• pascalxus 3y ago
  I'm so relieved someone is working on this. I mean, the cars of the 60s and 70s, many of them were so much lighter. Now all the sudden, cars have become fat and heavy and bloated. Of course it all comes down to consumer demand and regulations. I suspect Regulations have gone a long way towards making cars heavier and bigger and less efficient.
  • walthamstow 3y ago
    It's not just the US either. My house in London was built in 1970 and has a garage that will not fit a modern hatchback/compact in it. It might just about fit, but you wouldn't be able to open the doors.
    • kcplate 3y ago
      Guarantee you can’t find an American car built in 1970 that would fit either. Case in point, the 1970 Pontiac Bonneville Coup. A diminutive 2 door car that was a 18’ long by 6.5’ wide.
• TheLoafOfBread 3y ago
  During covid there was almost no car traffic in cities and it barely made a dent on emissions. So ICE or EVs, does not seem to matter.
• avalys 3y ago
  I hope you are not successful. Your policy is the wrong solution and will have side effects you cannot predict.
  • fifilura 3y ago
    Unfortunately you did not spell out what you were thinking. But I had a similar reaction. I believe that cars in general had less weight 40 years ago. But it came at a cost of much worse crash safety in form of deformation zones and general sturdyness. But I am sure the GP is also aware of these issues and can comment.
  • SketchySeaBeast 3y ago
    > Your policy is the wrong solution and will have side effects you cannot predict. Would you care to lay some of them out? I can see this being a problem with EVs, but I'm interested as to what you're thinking.
• sevenf0ur 3y ago
  Aren't EV batteries the heaviest part of a vehicle? It seems likely that cars will only get heavier as time goes on.
  • WorldMaker 3y ago
    Many of the least efficient vehicles like the EV Hummer the steel frame is still heavier than the battery. The efficiency game as EVs scale up will always try to get the highest range out of the fewest batteries/battery cells, so cars don't necessarily "only get heavier" because weight impacts efficiency (as does drag coefficients and overall surface area). Lower weight cars get more battery range from the same size battery. Also, while battery cells sometimes get heavier as the charge capacity gets denser, it is not a straightforward relationship. (Look at phone batteries over the last couple of decades: they store more charge than ever but are also effectively "lighter" in weight than ever.)
    • WorldMaker 3y ago
      Relatedly, because it is fun to speculate about other ways that battery weight may shrink in the next few decades though we don't have enough data yet: right now we're in a "range race" where manufacturers in the US, especially, are all focused on getting the highest possible range numbers (and thus more battery cells to cover it) that they can and meeting/exceeding the 300 miles per full charge "goal post" to fight Americans' current EV range anxieties. That "goal post" itself may shift, or at least open up to be more of a spectrum of consumer choice. As more Americans get more home charging infrastructure they may grow much more comfortable with smaller range batteries. The early Nissan Leafs have already shown that some home owners can successfully live on 100 miles per full charge or less batteries (even some road trips with current charging infrastructure). It may make sense for car manufacturers to compete on EV form factors that intentionally include smaller batteries and overall are much lighter-weight cars, if for no other reason than it is a way to drive costs down towards extremely cheap low end models. That's not entirely imaginary speculation either, because Asian markets with faster EV adoption curves than the US average already have some really interesting competition on light-weight, low-range, extremely cheap "urban" EVs. There's probably plenty of market potential in the US for sub-$10k low weight, low range EVs as at least secondary cars in households, and in some cases (some cities) would even already meet many primary car needs. It's just probably going to take a lot more infrastructure, marketing, and consumer convincing in the US market past current "range anxiety" over-concern before we see such cars common in the US, though.
• nateoearth 3y ago
  Strict weight limits would be hugely beneficial for addressing environmental, safety, and infrastructure cost concerns. A related--albeit more "out-there"--idea is to impose momentum limits in addition to speed limits based on vehicle weight classes. We have a crude version of this on highways, where speed limits for trucks are often lower than the limits for cars (e.g., 70mph for cars, 65mph for trucks). But I really like the idea of setting different speed limits for different weight classes of vehicles. Driving a Toyota Corolla? Let's call it a Class A vehicle (2,000-2,999 lbs), with a highway speed limit of 70mph. Driving a Jeep Grand Cherokee? That would be Class C (4,000-4,999 lbs), with a speed limit of 50mph. This would make roads a lot safer, and add an additional, non-monetary, tax on heavier vehicles. Another big benefit of imposing weight limits on consumer vehicles is that the United States would have a fighting chance of becoming energy independent, even before accounting for the shift to renewables. So we can add improved national security to the list of reasons to pursue this common-sense policy.
  • bryanmgreen 3y ago
    There is an interesting study that has shown SUV drivers tend to be overconfident, likely due to the vehicle size and their driving position, and are less able to judge the speed and capabilities of their vehicles accurately. [1] https://vehicledynamics.com/suvs-why-you-may-drive-fast/ https://vehicledynamics.com/suvs-why-you-may-drive-fast/
  • rascul 3y ago
    > But I really like the idea of setting different speed limits for different weight classes of vehicles. Driving a Toyota Corolla? Let's call it a Class A vehicle (2,000-2,999 lbs), with a highway speed limit of 70mph. Driving a Jeep Grand Cherokee? That would be Class C (4,000-4,999 lbs), with a speed limit of 50mph. This seems more dangerous, not less. Change a lane and all of a sudden you need to slam on your brakes because you didn't realize how much slower the other vehicle was going. Hopefully the person behind you can react quick enough. I see near accidents from this sort of thing fairly often with less of a speed difference.