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Comment by goda90 | Hacker News Reader

Not addressed: greater curb weight for the same size chassis means more momentum in crashes which means greater danger for occupants of other cars, pedestrians, cyclists, etc. Also it means greater wear and tear on tires and pavement, which itself is a source of pollution.

At the end of the day, EVs will be better than ICE, but they won't be a magic pill for all the problems caused by having lots and lots of cars.

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In a crash with a pedestrian I don't see how having greater momentum would make much difference compared to an ICE car. In both cases the mass of the car is so much more than the mass of the pedestrian that the difference in what they do to the pedestrian should be small.

For example, an ICE Ford F-150 that weighs 4500 pounds hitting a 200 pound pedestrian at 50 mph would nearly instantly accelerate that pedestrian to 47.9 mph.

Replace that ICE F-150 with a 6500 F-150 Lightning and the pedestrian gets nearly instantly accelerated to 48.5 mph.

Similarly, a 3800 pound ICE Ford Mustang would accelerate them to 47.5, whereas a 4800 pound EV Mustang would accelerate them to 48.0.

For a 100 pound pedestrian, it would be 48.9 mph and 49.2 mph for the ICE and EV F-150 respectively. For the ICE and EV Mustang it would be 48.7 mph and 49.0 mph respectively.

Low speed collisions are also similar. At 10 mph the ICE and EV Mustangs accelerate the 100 pound pedestrian to 9.7 mph and 9.8 mph respectively, and the 200 pound pedestrian to 9.5 mph and 9.6 mph respectively.

For the both the ICE and EV F-150 the 100 pound pedestrian accelerates to 9.8 mph (there is a difference, but it doesn't show up at the precision I'm using). For the 200 pound pedestrian it is 9.6 mph for the ICE and 9.7 mph for the EV.

To add to the weight problem, in my country (NL), road tax is calculated based on the weight of the car, not the amount of kilometers driven, although VAT and excise on fuel do compensate for that. That said, road tax is included in fuel costs over in Germany.

That said, the long-term theory of EVs is sound; if they have the right sensors and if they're interconnected with each other, more accidents will become preventable and the net result is a safer environment. But that's the theoretical outcome.

It's not theoretical, and you don't need them to talk to each other to reduce accidents. Nor is the tech you mention necessarily unique to EVs. There's evidence already that the safety features shipping on modern cars, including collision warning, avoidance, cross traffic alerts, etc. are already helping to reduce accidents. Where EVs can help here on safety is encouraging people to drive more slowly (due to efficiency concerns) and also advanced in motor traction control that is not possible on an ICE vehicle. The rest is not unique to EVs.

The YouTuber Not Just Bikes recently put out a video arguing that self driving cars will allow for and encourage policy and urban design that is even worse than current car-centric cities. Maybe too sensationalist, but they are interesting points to consider. https://www.youtube.com/watch?v=040ejWnFkj0

It does seem clear to me that the solution to "self driving cars that rely on an interconnected communication network to maximize driving efficiency sometimes run into jaywalkers and bikers" is banning jaywalkers and bikers for many car first people. Probably will lead to even more cultural divide between sun belt and non sun belt dwellers. Even my city of chicago which is easily top 5 best city for non car transportation in the US is very pro car politically. I could easily see the city government going for the ban all non cars from streets route

But self driving has almost nothing to do with EVs. One could build all interconnected self-driving cars without all of them being EVs...

The greater wear on tires issue is over stated. By far the greatest impact on tire wear is how you drive. My first set of all seasons in my BMW i4 M50 went more than 25k miles.

The cars being heavy issue may get better due to EVs longer term due to it bringing more attention to efficiency and manufacturers prioriting efficiency more. Additionally, some EVs are not notably heavier than ICE cars in their class; eg Tesla Model 3 and Model Y.

Only 25k miles? Kinda low for daily driver tires where 40k+ is common.

> greater curb weight for the same size chassis

A Tesla Model 3 and a BMW 3 are approximately the same weight, their weight ranges overlap.

Both are too heavy. It's a weight war out there because everyone has to defend against being T-Boned by a pickup truck.

Rivian R1T is approximately 2,000 lbs heaver than a Chevy Silverado, and it's less useful.

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