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Scientists: Electric Vehicles Produce As Many Toxins As Dirty Diesels (dailymail.co.uk)
An anonymous reader writes: Thanks to ongoing efforts to reduce engine emissions, nowadays only 10% to 15% of particulate emissions from traffic are coming from vehicles' tailpipes. The remainder originates in tire, road surface and brake wear. A study by Victor Timmers and Peter Achten published in Atmospheric Environment has now found that the extra weight of electric vehicles causes non-tailpipe emissions to increase by about as much as the omission of the internal combustion engine saves. Atmospheric particulates have been shown to cause cancer, cardiovascular disease and respiratory diseases and are widely considered as the most harmful form of air pollution. Achten said, "We found that non-exhaust emissions, from brakes, tires and the road, are far larger than exhaust emissions in all modern cars. These are more toxic than emissions from modern engines so they are likely to be key factors in the extra heart attacks, strokes and asthma attacks seen when air pollution levels surge." The study shows that non-exhaust emissions a vehicle produces is directly related to its weight. Scientists found that electric and eco-friendly vehicles weighed around 24 percent more than conventional vehicles, which in turn contributes to more wear on the tires.
Can a legitimate news outlet tell us if this is a REAL concern?
the Petroleum Institute and Oil Producing Export Countries.
Who knew that stuff was so deadly toxic? Really?
First off, electric cars use their brake pads less, not more. Regenerative brakes do most of the work, and the brakes last 2-3x longer than a regular gasoline car. Tire do last a little less long, but most of those are big particles, and I have never heard of tire dust being considered a major health risk.
Sounds like a hatchet job...
Doing a two minute google search turns out the authors are an undergrad university student (according to LinkedIn) without a research background (google scholar turns empty), and a researcher with a company that develops combustion engines
Not to pull an ad-hominem here, but I'd take the paper with lots of grains of salt.
As a savvy owner of a Prius c hybrid, I think I have some insight into this... Basically, the brake pads *are* used quite a lot by aggressive drivers who tailgate and have to brake hard when the car in front of them slows down. People who drive with a proper following distance ahead of them will rarely have to use the disc brakes.
Hybrid vehicles (and EVs, probably) have smaller brake pads than similarly sized conventional vehicles (though the actual stopping power of the disc brakes in an emergency is just as good as regular cars). The brake pads are about half as thick on my Prius c as the brake pads on my Honda Civic. That's because the manufacturer expects you to use them less often. I'm sure there are some insane drivers out there who can burn through the brake pads on a vehicle like mine in well under 50,000 miles, but those same people would burn through the brakes on any vehicle just as quickly.
I've learned to "feel" the difference between the cut-over between regenerative braking and the disc brakes. The disc brakes slow you down WAY faster. There's not a discrete and obvious jolt when you gradually depress the brake pedal; it's incredibly smooth; but to use an analogy, as long as I'm slowing down at about the same rate as a truck can slow down when using the jake brake (engine braking - that loud "farting" sound that large trucks sometimes make when slowing down), I'm using the regenerative braking system only. If I'm slowing down much faster than that, the disc brakes are being engaged (the brakes and the regenerative braking can be active at the same time, unless you are braking at what would be considered "emergency" speeds, in which case the regenerative braking system disengages, perhaps because it can't handle that amount of torque or current).
As for the article itself: 24 percent?! That's total bullshit.
The Prius c is literally a Yaris Hybrid (it's marketed as such in some parts of the world). It's the Toyota Yaris -- a compact car -- with the Toyota Hybrid Synergy Drive in it. So, it's a Yaris, *plus* the weight of the HSD.
The curb weight of the Yaris is 2335 pounds. The curb weight of the Prius c is 2500 pounds. That's only a 7.066% increase. That's a far, far cry from the 24% the article cites.
OK, you say, let's look at *electric* vehicles specifically, not just hybrids. Because hybrids don't have to lug around 500 pounds of lithium-ion batteries. Hybrid batteries tend to weigh under 200 pounds, with the smallest hybrids' ~1 kWh batteries weighing less than 100 pounds.
Let's take the Chevy Spark. The conventional Spark weighs in around 2270 pounds. The EV? 3000 pounds. That's a 32% increase for basically the same passenger and cargo volume. Fair enough. But 3000 pounds isn't out of this world, and is in the ballpark of many upscale compact cars like the (conventional) Honda Civic.
Another example. The 2016 Nissan Leaf weighs around 3150 pounds. I did some research to try and find a conventional vehicle with similar interior measurements (headroom, cargo space, etc.) and I came up with this: The 2016 Honda Civic EX has a total (usable) interior volume of 110.1 cubic feet with a curb weight of 2799 pounds. The 2016 Nissan Leaf has an interior volume of 116 cubic feet. So for 6 more cubic feet of interior (5.4% more), the vehicle weighs 351 pounds (25.4%) more.
Based on these limited comparisons, it seems like the article's claim about the increased weight of electric vehicles is factual. However, it is absolutely not valid to make the leap to saying that plug-in hybrids or conventional hybrids are anywhere near as bad in terms of added weight.
What I'm not convinced of, however, is the severity and environmental impact of tire and brake wear, regardless of vehicle weight. EVs and hybrids also run with low rolling resistance tires, which should reduce the amount of tire "stuff" in the air, in any case. Did they take that into account?
However, switching out a gasoline engine for a TDI diesel engine adds about 300 pounds to a sedan-
http://31.184.194.81/10.1016/j... = Sci-hub link.
It's absolute garbage "research". Speculation layered upon speculation. It has the quality of a rant.
Victor Timmers is still getting his BEng. He was a research intern. Yay!
https://www.linkedin.com/in/vi...
Peter A.J. Achten is a hydraulics engineer for INNAS.
http://www.innas.com/
Some gems from their trash:
"Despite the lack of direct research, there is significant indirect evidence..."
"Many studies and emission inventories suggest..."
But here's my favorite:
"It can be hypothesised that..."
WTF?
Why is The Daily Mail, a lowest-rung tabloid, being linked on the /. main page?
The paper itself is so full of faults that I would have to write more than the paper's authors in order to describe them all. Others in this thread are doing that. I will take the time to make two counter-points, though:
(1) Heavier cars, eh? You mean, like SUVs? The logical conclusion here is to promote sub-compact cars, public transport, and cargo transport by rail, rather than big-rig transport, of goods around the country. I don't think Rupert Murdoch would be in favor any of this, considering his investments in the fossil fuel industry.
(2) Electric cars rely primarily on regenerative braking. Essentially, the motors work in reverse to produce electricity when reducing speed (momentum, but ultimately kinetic energy) of the car – transforming that back into potential energy that is stored in the car's batteries. These motors are brush-less, meaning that there is no frictional contact, and thus no particulates produced. Compare this to regular car brakes, which are entirely frictional and heat-dissipating. Do we still use asbestos in car brake drums? Regardless, 'regular' brakes are two surfaces grinding against each other, creating micro-particulates. Drum brakes are going away, so it's all 4-wheel disk brakes. Usually made of metal.
But on my high-end sports car, which requires ceramic brake pads, braking creates micro-particulates of ceramic materials that are not soluble in the human lung, which is the kind of thing that causes mesothelioma (blacklung, asbestosis, silicosis, and the many others yet to be named... until enough people exhibit direct signs of a specific material causing the mesothelioma). It's not hard to know which materials will be in this class, but my managers tended to 'shush' me when I brought up the topic years ago – but it has since-then become a major area of research. It is not hard to create a definitive list, but NSF only likes to fund incremental research, rather than fundamentals-based studies. Thus, I will simply keep my mouth (and my windows) shut.
Articles like this are almost as popular with news sites as "chocolate/beer/wine/cheese/bacon cures cancer!". From what I can tell, the publication was written by a summer intern who is about a junior in college, by reviewing other publications and making some guesses from the data contained therein. It's a good thought piece, i.e. "Hey guys, there's a lot of stuff that we haven't really done much to improve yet, maybe we should look into that." The publication doesn't make an argument that "electric cars are evil." It doesn't even have any real data of its own. And well over half of the particulate matter that they attribute is just stuff that was lying on the ground and the cars kicked up into the air; and because they claim that an EV is 24% heavier, it will kick up 24% more PM in its wake, which is probably not true. I'd be willing to bet that even if EVs average 24% heavier, they are probably not also 24% larger and 24% less aerodynamic; and the size and shape of the vehicle matter at least as much as the weight in creating a wake, if not more.
On top of that, I don't know that reduction of particulate matter has ever been a huge concern for the EV market. Generally, the concerns are more along the lines of reducing CO2 (/CO/NOx/HCHO/NMOG/NMHC) emissions, oil consumption, monetary support to unfriendly OPEC nations, required maintenance, or fuel costs; or increasing support of new technology, renewable energy, etc. But, PM is certainly a health concern, so maybe the article's best use is just to point out that, as long as we're making a lot of other changes in our transportation system, maybe we should consider how we can change it to reduce PM emissions as well.
TL;DR: Science reporting fails again.