5 ms·
Brake regeneration is a large part of the braking force for many EVs when the brake pedal is pressed, so the brake pads in some EV cars are actually smaller tha
by vlad 10y ago
Brake regeneration is a large part of the braking force for many EVs when the brake pedal is pressed, so the brake pads in some EV cars are actually smaller than their gas siblings.
Brake regeneration also avoids using the brake pedal altogether in many cases because an EV slows down significantly when the gas pedal is released.
With electric power, smaller brake pads, and less need to use them, I'm surprised the article believes there is only a 1% reduction in overall particle pollution for EV's vs. gas cars.
Plus, a typical EV is a small and modern 0-2 year old car compared to the gas vehicles out there, such as a 7-year-old, inefficient, v8 engine SUV.
- maxerickson 10y agoA big factor is that gasoline engines don't release all that much particulates.
- vlad 10y ago"Electric-powered vehicles, of course, have no exhaust emissions. However, because they’re 24 percent heavier on average, the study found that EVs shed more particulate matter from tires and brakes, and also kick up more particulate matter from road surfaces." If the brake pads are smaller and aren't required to slow down in many cases, the EV should win, especially when the average EV on the street is likely similar in weight compared to an average non-EV vehicle. As far as kicking up existing particulate matter, EV's shouldn't be penalized for kicking up dust on the road which came from others cars, which are almost entirely non-EV cars and 18-wheelers. I bet there are other more significant factors to derive impact on pollution from EVs than brake dust, such as the source of electricity used to charge them. I'll try to look at the study later to see how the 1% difference between road pollution between gas and EV vehicles was calculated.
- deleted 10y ago[deleted]
- maxsilver 10y ago> "However, because they’re 24 percent heavier on average, the study found that EVs shed more particulate" That's a pretty misleading statistic too. EV's are 24% heaver than the average subcompact. But most people are already driving cars significantly heavier than the lightest subcompacts. According to the EPA, the actual average personal vehicle weight was 3,977 pounds in 2012. That is heavier than most EV's -- it's heavier than any Chevy Bolt, Volt, or Nissan Leaf ever sold. For example, a 2017 Volt is lighter than a similarly-priced 2017 Avalon, even though the Volt has a 18.4kWH battery in it, does 53 miles zero-emission electric, and gets an extra 15mpg when using gasoline.
- selimthegrim 10y agoThe new GDI engines most certainly will...
- webreac 10y agoThis small reduction of particle pollution was the result of a very old study. At that time, there was no brake regeneration and the car was very heavy. I guess there is no recent study because the result would be obvious.
- handedness 10y agoSee my post above for a study from 2016.
- handedness 10y agoPad size is irrelevant, and smaller pad sizes can actually result in faster release of material. Regeneration is certainly a benefit, but in my experience with a few different EVs caps out at fairly low levels of braking. Also, I don't know anyone who's replaced a V8 SUV with an EV. Most of the EV-owning people I know replaced hybrids, generally Priuses. You may be right, but I'd like to see a source that runs contrary to this instead of pure conjecture: http://www.sciencedirect.com/science/article/pii/S135223101630187X http://www.sciencedirect.com/science/article/pii/S1352231016...