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My big fear is weight. Road damage scales with the per-axle weight raised to the 4th power. EVs are quite heavy to compensate for the lower energy density of li

My big fear is weight. Road damage scales with the per-axle weight raised to the 4th power. EVs are quite heavy to compensate for the lower energy density of lithium ion batteries.

_ph_ 8y ago
Electric cars are not that much heavier than ICE cars. The Model 3 is pretty much on par with its gasoline competition. The real road killers are not passenger cars, but heavy trucks and semis. They have a multiple per-axle weight of any car.
- leetcrew 8y ago
  > Electric cars are not that much heavier than ICE cars. this isn't really true. a model 3 is about 400lbs heavier than a base a4 (~12%) and 300lbs heavier than a base 3 series (~8%). that's a pretty big difference for a midsize sedan. your overall point is valid, of course. any sedan is going to do negligible damage compared to a large truck.
  - _ph_ 8y ago
    The base models of the named cars have of course much less powerful engines than the Model 3, so the weight difference goes down as you equip the ICEs with larger engines. Yes, some weight differential is left, but a small one compared to trucks and semis.
    - leetcrew 8y ago
      the engines of the named cars are essentially on par with the lowest specced (and lightest) model 3 that's currently available. the only situation where the model 3 has a strong advantage is in sprints from 0-60, a number most people pay entirely too much attention to in my opinion. edit: I'm actually wrong, according to car and driver, the 0-60 numbers are really close on all three cars. I don't want to digress too far on the performance characteristics of the cars, as this starts to be a bit subjective.
  - village-idiot 8y ago
    Also, it’s not like EV semitrucks will be lighter than their diesel brethren, will they?
    - bluGill 8y ago
      They will probably be the same since the limit on weight is the road not the truck. The only question is what difference in cargo capacity there will be.
      - village-idiot 8y ago
        Less cargo, more trucks.
  - freehunter 8y ago
    300-400lbs is the weight of two passengers. If we were that worried about per-axle weight on the roads, we wouldn't try to encourage HOV lanes or carpooling, since more people in one car increases per-axle weight.
    - leetcrew 8y ago
      honestly not sure what point you are trying to make here. a model 3 with two passengers will still be 300-400lbs heavier than the cars I mentioned. yes, passengers also add a significant amount of weight to a car, but not enough to damage the road as much three separate midsize sedans.
      - freehunter 8y ago
        My point is that 300-400lbs isn't significant in the grand scheme of things. There are plenty of things that add weight to cars that no one mentions. It's hard to then argue that electric cars are too heavy to be mass-market. No one is advocating for fewer passengers per car, even though each passenger adds weight. In fact, we prefer more passengers per car because (among other things) it is fewer engines pumping out pollutants. The same can be said about electric cars. Yet electric cars are getting complains about another 300-400 lbs, but gasoline-powered carpools are not. No one here has complained about the added weight of the unnecessary cargo most people carry. No one is mentioning the weight of a full tank of gasoline (an average full tank is ~100 lbs) and advocating for smaller tanks or to run with just enough fuel to get to your destination. Air bags and anti-lock brakes and automatic transmissions and air conditioning and stereo systems all add significant weight to the car. No one would advocate removing those things from cars. No one complains about the added weight of things designed to make cars more fuel efficient because we like the fuel efficiency. Yet batteries do just that, and here we are. My point is, arguing that electric cars have a problem because they're as heavy as a gasoline powered car (with no gasoline in it, since curb weight is empty) with two passengers is disingenuous at best and harmful at worst. It's a complete non-argument. Especially when passenger cars are some of the lightest vehicles on the road, by an impressively huge margin. An electric car may be 12% heavier than a gasoline car, but a semi truck is still 1600% heavier than that.
sokoloff 8y ago
Taking a 4000 pound car (typical mid-sized sedan) and ballooning the weight to 5000 pounds (Tesla S) is 2.5x the road damage. (Tesla 3 is ~4000 pounds vs the 3600 of a comparable A4, so a factor of ~1.5x.) By comparison, four 16000# axles on a trailer are 8192 times the road damage per mile (and likely drive a lot more miles) of the 4000# sedan.
- village-idiot 8y ago
  I agree that semi trucks represent a massive amount of road damage, and iirc the way we structure our road costs represents a $60B transfer of wealth to the trucking industry. I wish we’d reverse that, as we could then start seriously looking at trains as a more reasonable means of moving most of our bulk goods. Of course, it’s not like EV semitrucks won’t have the same weight issues as passenger cars. The same issues with energy density apply there too. EV semitrucks will either need to be heavier or more plentiful to compensate for the loss of range or towing capacity compared to diesel. As an aside, we need to revisit the 4,000lb standard for sedans. The heaviest Honda Civic weighs 3,000lb, my Mazda 3 weighs under 3,000lb, and a Mazda 6 weighs at most 3,500lb. These days you need a luxury or performance sedan before you start touching the 4,000lb mark.
  - freehunter 8y ago
    >we need to revisit the 4,000lb standard for sedans Agreed. A quick Google search shows the average US vehicle is 4,000 lbs or above, but that includes vans and trucks and SUVs. The average sedan is closer to or below 3500 lbs.
  - sokoloff 8y ago
    > These days you need a luxury or performance sedan before you start touching the 4,000lb mark. Agreed. I picked 4000# as the reference against a Model S (which clearly competes more with an A6 or E-class than a Civic) and the Model 3 I compare more to an A4.
    - village-idiot 8y ago
gameswithgo 8y ago
Model S and Model 3 are very nearly the same mass as their gasoline competitors.

My big fear is weight. Road damage scales with the per-axle weight raised to the 4th power. EVs are quite heavy to compensate for the lower energy density of lithium ion batteries.

_ph_ 8y ago

Electric cars are not that much heavier than ICE cars. The Model 3 is pretty much on par with its gasoline competition. The real road killers are not passenger cars, but heavy trucks and semis. They have a multiple per-axle weight of any car.

leetcrew 8y ago
> Electric cars are not that much heavier than ICE cars. this isn't really true. a model 3 is about 400lbs heavier than a base a4 (~12%) and 300lbs heavier than a base 3 series (~8%). that's a pretty big difference for a midsize sedan. your overall point is valid, of course. any sedan is going to do negligible damage compared to a large truck.
- _ph_ 8y ago
  The base models of the named cars have of course much less powerful engines than the Model 3, so the weight difference goes down as you equip the ICEs with larger engines. Yes, some weight differential is left, but a small one compared to trucks and semis.
  - leetcrew 8y ago
    the engines of the named cars are essentially on par with the lowest specced (and lightest) model 3 that's currently available. the only situation where the model 3 has a strong advantage is in sprints from 0-60, a number most people pay entirely too much attention to in my opinion. edit: I'm actually wrong, according to car and driver, the 0-60 numbers are really close on all three cars. I don't want to digress too far on the performance characteristics of the cars, as this starts to be a bit subjective.
- village-idiot 8y ago
  Also, it’s not like EV semitrucks will be lighter than their diesel brethren, will they?
  - bluGill 8y ago
    They will probably be the same since the limit on weight is the road not the truck. The only question is what difference in cargo capacity there will be.
    - village-idiot 8y ago
      Less cargo, more trucks.
- freehunter 8y ago
  300-400lbs is the weight of two passengers. If we were that worried about per-axle weight on the roads, we wouldn't try to encourage HOV lanes or carpooling, since more people in one car increases per-axle weight.
  - leetcrew 8y ago
    honestly not sure what point you are trying to make here. a model 3 with two passengers will still be 300-400lbs heavier than the cars I mentioned. yes, passengers also add a significant amount of weight to a car, but not enough to damage the road as much three separate midsize sedans.
    - freehunter 8y ago
      My point is that 300-400lbs isn't significant in the grand scheme of things. There are plenty of things that add weight to cars that no one mentions. It's hard to then argue that electric cars are too heavy to be mass-market. No one is advocating for fewer passengers per car, even though each passenger adds weight. In fact, we prefer more passengers per car because (among other things) it is fewer engines pumping out pollutants. The same can be said about electric cars. Yet electric cars are getting complains about another 300-400 lbs, but gasoline-powered carpools are not. No one here has complained about the added weight of the unnecessary cargo most people carry. No one is mentioning the weight of a full tank of gasoline (an average full tank is ~100 lbs) and advocating for smaller tanks or to run with just enough fuel to get to your destination. Air bags and anti-lock brakes and automatic transmissions and air conditioning and stereo systems all add significant weight to the car. No one would advocate removing those things from cars. No one complains about the added weight of things designed to make cars more fuel efficient because we like the fuel efficiency. Yet batteries do just that, and here we are. My point is, arguing that electric cars have a problem because they're as heavy as a gasoline powered car (with no gasoline in it, since curb weight is empty) with two passengers is disingenuous at best and harmful at worst. It's a complete non-argument. Especially when passenger cars are some of the lightest vehicles on the road, by an impressively huge margin. An electric car may be 12% heavier than a gasoline car, but a semi truck is still 1600% heavier than that.

sokoloff 8y ago

Taking a 4000 pound car (typical mid-sized sedan) and ballooning the weight to 5000 pounds (Tesla S) is 2.5x the road damage. (Tesla 3 is ~4000 pounds vs the 3600 of a comparable A4, so a factor of ~1.5x.) By comparison, four 16000# axles on a trailer are 8192 times the road damage per mile (and likely drive a lot more miles) of the 4000# sedan.

village-idiot 8y ago
I agree that semi trucks represent a massive amount of road damage, and iirc the way we structure our road costs represents a $60B transfer of wealth to the trucking industry. I wish we’d reverse that, as we could then start seriously looking at trains as a more reasonable means of moving most of our bulk goods. Of course, it’s not like EV semitrucks won’t have the same weight issues as passenger cars. The same issues with energy density apply there too. EV semitrucks will either need to be heavier or more plentiful to compensate for the loss of range or towing capacity compared to diesel. As an aside, we need to revisit the 4,000lb standard for sedans. The heaviest Honda Civic weighs 3,000lb, my Mazda 3 weighs under 3,000lb, and a Mazda 6 weighs at most 3,500lb. These days you need a luxury or performance sedan before you start touching the 4,000lb mark.
- freehunter 8y ago
  >we need to revisit the 4,000lb standard for sedans Agreed. A quick Google search shows the average US vehicle is 4,000 lbs or above, but that includes vans and trucks and SUVs. The average sedan is closer to or below 3500 lbs.
- sokoloff 8y ago
  > These days you need a luxury or performance sedan before you start touching the 4,000lb mark. Agreed. I picked 4000# as the reference against a Model S (which clearly competes more with an A6 or E-class than a Civic) and the Model 3 I compare more to an A4.
  - village-idiot 8y ago

gameswithgo 8y ago

Model S and Model 3 are very nearly the same mass as their gasoline competitors.