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EPA’s car pollution rules would save Americans trillions of dollars

Posted on 10 May 2023 by dana1981

This is a re-post from Yale Climate Connections

Electric vehicle (EV) sales are surging in many countries around the world, including the United States. According to the Department of Energy, EVs accounted for just 1% of new U.S. car sales in 2017. That share surpassed 3% in 2021 and approached 6% in 2022. Though the U.S. remains well below the global average EV share of new car sales, which exceeded 14% in 2022, the American market is catching up fast. According to an analysis of global markets by Bloomberg, a 5% share appears to be a tipping point at which EV sales take off in most countries.

Amid this rapidly rising EV adoption, the Biden administration in an August 2021 executive order tasked the Environmental Protection Agency with extending its vehicle tailpipe pollution regulations for vehicle model years 2027 through at least 2030. The previous EPA rules, revised in late 2021, only applied to model years through 2026. These rules set the average amount of carbon and other air pollutants that the vehicles sold by automakers are allowed to emit in a given sales year.

With EV sales surging, their prices rapidly falling, and their net pollutant emissions being substantially lower than fossil-fueled cars, the EPA saw an opportunity to issue much more stringent vehicle emissions regulations without creating any undue economic burdens associated with car ownership costs. Quite the opposite in fact — in its 758-page proposed rules for vehicle model years 2027—2032, EPA conservatively estimates that climate, health, and vehicle cost savings for Americans will substantially exceed $1 trillion* over the next three decades.

* Note that the estimated benefits in this article are present values using a 3% discount rate.

EVs will save car owners money

Many automakers have announced aggressive EV sales targets. For example, GM — which has the largest share of the U.S. auto sales market — aspires for 100% of its car sales to be EVs in 2035. If all automakers’ targets are met, EVs will account for nearly 50% of new U.S. car sales in 2030.

In its proposed tailpipe rules, the EPA estimates that the U.S. auto market is on track for EVs to account for 30—60% (most likely about 40%) of new car sales in 2030, depending on factors like battery prices and cultural acceptance of the technology. The agency estimates that to meet its proposed vehicle pollution rules, automakers will need to reach the upper end of the expected range, with EVs comprising 60% of new U.S. car sales in 2030 and 67% in 2032.

A chart shows that if EPA's rules are implemented, EV sales will accelerate, reaching 70% of new U.S. auto sales by 2032. The EV share of new U.S. car, SUV, and light-duty truck sales to date (black), in the most likely business-as-usual scenario (gray), and if EPA’s proposed new vehicle pollution regulations are adopted (green). Created by Dana Nuccitelli from data in EPA’s proposed new rules.

So far, EV sticker prices have tended to remain higher than their gasoline-fueled counterparts, although some EV models are approaching price parity. As a result, the EPA estimates that rising EV adoption will increase the average new vehicle purchase price by about $1,000 in the early 2030s. But that doesn’t account for the tax credits of up to $7,500 for new EVs included in the Inflation Reduction Act or their fuel and maintenance cost savings.

Based on average U.S. electricity and gasoline prices over the past decade and average vehicle efficiencies, fueling an EV costs about 5 cents per mile driven, compared to over 12 cents per mile for a gasoline-fueled car. For the average American who drives over 14,000 miles per year, the EV fuel savings alone would amount to nearly $1,000 per year. And because EVs have far fewer parts that can wear down and break, EPA estimates that EVs will save car owners over $1,100 per year in fuel, maintenance, and repair costs.

Overall, even when accounting for the costs of installing many more EV charging stations, the EPA estimates that the increased EV adoption resulting from its new rules will reduce U.S. vehicle ownership costs by a total of more than $1 trillion over the next three decades.

EVs will reduce climate pollution and damages

The EPA’s proposed tailpipe rules would require that automakers reduce the average carbon pollution from cars, SUVs, and light-duty trucks by more than half between 2027 and 2032. Light-duty vehicle sales from automakers will be allowed to average no more than 82 grams of carbon dioxide per mile traveled in 2032, down from 186 grams per mile in 2026.

a chart shows grams of carbon dioxide per mile falling between 2026 and 2032 under a number of similar scenarios Light-duty fleet average carbon dioxide emissions per mile under existing rules (dashed line), EPA’s proposed new rules (black line), and three similar alternative EPA proposals (gray lines). Source: EPA’s proposed new rules.

Though automakers can meet those carbon pollution standards however they choose, accelerating EV sales are likely to be the primary solution. That’s because electric motors are much more energy-efficient than gasoline combustion engines, which lose a lot of energy in the form of waste heat, and because the electric grid is rapidly decarbonizing.

The economic benefits of reduced climate damages caused by carbon pollution are estimated using what’s known as the “social cost of carbon.” An interagency working group is in the process of updating the federal government’s estimate of that number. During the Obama administration, it was estimated at around $51 per ton of carbon dioxide pollution, but recent research incorporating the latest climate science and economics literature puts the value at closer to $185 per ton.

Using the $51 per ton value, the EPA estimated that its proposed vehicle tailpipe rules will yield $330 billion in avoided climate damages globally over the next three decades. But using an updated social cost of carbon would increase that value to around $1 trillion.

EVs will reduce air pollution and health care costs

The EPA’s proposed rules also limit tailpipe emissions of other air pollutants. These would reduce vehicle small particulate matter (often called PM2.5) emissions by over 95% and nitrogen oxide and non-methane organic gas emissions by 60% by 2032. As the EPA notes in its proposed rules, “PM2.5 is associated with premature death and serious health effects such as hospital admissions due to respiratory and cardiovascular illnesses, nonfatal heart attacks, aggravated asthma, and decreased lung function.”

As a result, the estimated health benefits of reducing these tailpipe air pollutants are substantial. The EPA estimates that they would avoid about 1,000 premature deaths over the next three decades and yield health benefits totaling between $140 billion and $280 billion.

Climate and health modeling expert Drew Shindell at Duke University’s Nicholas School for the Environment described EPA’s health benefits estimates as “both reasonable and likely too low.”

Shindell may review the proposed new tailpipe regulations as a member of EPA’s Science Advisory Board but provided his personal opinions about the rules via email.

In his own research, Shindell has incorporated data from a broader set of countries than the EPA considered — the agency focused on studies from the U.S. and Canada. His team’s results suggested that the effects of air pollution may be roughly twice as bad as previously estimated. Shindell also noted that the EPA only includes health impacts for which there is clear evidence of a causal effect, but evidence suggests that air pollution causes substantially more illness and death through pathways that are not yet well understood.

“Again, it’s a reasonable choice on EPA’s part to include only those endpoints for which the data is extremely clear,” Shindell wrote, “but likely to lead to an undercount.”

A financial, climate, and health win-win-win

Adding it all up, the EPA estimates that its rules will save about $1.6 trillion in vehicle costs, climate damages, and health impacts between 2027 and 2055. Updating the social cost of carbon would boost those savings to well over $2 trillion, and as noted by Shindell, the health savings could also be substantially higher than EPA’s estimates, raising the rule’s total benefits close to $2.5 trillion.

In short, by accelerating the transition to EVs, EPA’s new tailpipe pollution rules could benefit Americans’ bank accounts and health while helping to curb the climate crisis.

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Comments 1 to 10:

  1. Just one comment of man possible.  The 12c/mile includes Federal and state taxes to maintain roads.  The 5c/mile for electrics does not.  They just sort of forgot about that.  

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  2. 758 page EPA "proposed rules" link above is broken.  I tried looking the same document up and found other sites with the same link like this They describe some more of the quantitative benefits in that document.

    I have a question however.  Have the vehicle emissions been segmented into tailpipe and non-tailpipe?  In this source they say "Thus, non-exhaust sources, including brake and tire wear PM, have become larger contributors to traffic-related emissions as well as to ambient PM2.5 (particles less than 2.5 um) concentrations."

    Another question is hormesis.  There's a J-curve to many things like particulates.  There's a slight detriment to having none, then a benefit at low amounts, then more detrimental at increasing amounts and very detrimental at high amounts.  Figuring out where people are on the curve will change the costs and benefits for various groups.  City dwellers will always have more pollution but will also (and have also) benefitted the most from EVs.  I can't tell if they did that segmentation or not.

    Final question is how soon to transition for various groups considering the grid mix.  In some places it will make sense to wait considering the battery will be worn out with charge cycles before the grid has been transitioned away from mostly fossil.  The segementation by group could probably be applied by county based on vehicle-mile density and grid fuel mix.

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  3. Eric, thank you for the links.

    I suspect that the PM2.5 from rubber is not easily reducible.  However, PM2.5 from brake pads could well be an area of improvement, if research effort is put into it.

    Bobhisey, it would be interesting to see more details about the 5c/mile and 12c/mile figures ~ surely there would be vast differences from country to country.  Taxes vary a lot, and a cynic would point out that funding nominally earmarked for road maintenance . . . somehow gets bled off into "general revenue".  Local regional taxation can also go into road repairs, often combined with federal grants.  It's very often a mish-mash.

    At worst, it sounds (to me) like the overall costings situation is likely close to being a wash.  And there is still much scope for future battery improvements in cost & performance (and possibly a smaller EV battery combined with a fuel-cell range extender).  But you are right ~ death & taxes will never be out of the picture.

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  4. Eric,

    My Tesla Model 3 uses the motor for almost all of the braking.  I will be very surprised if the vehcle ever requires new brake pads.  I have read that many other (most? All?) electric cars primarily use the motor for braking since they generate electricity to increase driving range.  Can you provide a reference that says electric cars will wear out brake pads faster than ICE cars?  Even hybrids use regenerated braking to increase range.

    What do other model electric car users who read SkS find about brake use?  All Teslas primarily use regenerative braking with the engine and not brake pads.

    I have heard a little about tire wear.  My niece, who is a environmental  scientist working on land management, had never heard of this type of pollution, which suggests to me that it is not very important.  Can you provide a link that describes the importance of electric cars versus ICE and tire wear?  I expect that tire manufactures will reformulate tires to reduce wear if it is a problem, how much that would help is another question.

    I notice that fossil fuel proponents raise a lot of red herrings about electric cars, like brake pad and tire wear.  Are these really issues or are they fossil propaganda?

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  5. Please note that there has been previous discussion of EVs on this thread, and that the distinction between "emissions" from tailpipes vs tires, etc. was brought up in this comment and the ones that follow. Distinguishing between gas emissions (such as CO2) and particulate emissions (such as soot, etc - the things that show up as find particles measured by PM2.5) is very important. In the reference listed on the above thread, tire wear is largely related to vehicle weight, not the source of power.

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  6. Michael @4 , in my role of Devil's Advocate, I can confidently and citationlessly point to the heavier mass of EV's . . . combined with their often temptingly brisk acceleration . . . that leads to faster tread wear.  And presumably the rubbery engineers prioritize grip & low rolling resistance & quietness for the EV market, and tread life is much lower on the list.  The attention to particle PM2.5 pollution has been as an exhaust concern, rather than a rubber concern (even among youthful environmental scientists).  But perhaps this could change in the future.

    It is all very well for you Teslarazzi  to use regenerative braking.  But for those of us with more Scottish blood (read:  pessimistic & dour & penny-pinching) tend to use the disk brakes far more.  The line of thought is that ~ with today's primitive lithium batteries, we wish to avoid the frequent reversals of current flow which shorten battery life.  New battery technology (with ultra-high cycling life and low capital cost) may come eventually . . . but for now, us penny-pinchers would like to eke out the battery long enough to get the rest of the car up to its economic life (rust & plastics degradation) in 15 years or more.  Aye, and a chance at 20.

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  7. Michael thanks for the generative braking reminder.  I forgot about that. 

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  8. Reading Eric's link about Brake and tire dust I noticed that they always said "brake and tire".  That suggests to me that brake dust is more important.  The article suggests that this research is just beginning because ICE pollution used to be so much bigger that people did not bother looking at brakes and tires.

    I Goggled a little and found that a lot of EV's use one pedal driving.  I have found that with one pedal driving I rarely use the brakes.  I have not measured but I would estimate much less than 5% of the time.  It appears that all electric cars use regenerative brakes.  The brake wear from electric cars will be much lower than current ICE cars.  I saw a youtube video (what could be more accurate ;) where after 90,000 miles (about 145,000 Km) the brake pads were about 15% worn.  Google says brake pads should be replaced every 20,000 miles, although some pads last longer.

    The mechanic estimated that the tires had been driven 65,000 miles and had 5,000 miles left on them.  The car was a Tesla model.   70,000 miles is not much different than an ICE car tire wear.  I note that when you buy tires some have much longer warranty milage claims than other tires.  Presumably tires with a longer lifetime release less dust per mile.  The size of the dust particles is probably also different but I have no idea what the differences are.

    My conclusion is that elecric cars release much less brake dust and probably a little more tire dust than ICE cars.   Since these are currently not even measured because ICE cars release so much particle pollution, switching to electric cars will dramatically reduce small particle pollution.

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  9. My two cents worth on tire wear.

    "A Tesla Model 3 Performance with AWD weighs 4,065 pounds — 379 pounds more than a BMW 330i XDrive (A typical similar size and quality of ICE car to the best of my recollection).

    This weight difference is not going to cause much additional tire wear , so its not significant for vehicle running costs. These sorts of objections to EV's seem trivial to me.

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  10. Nigelj,

    I have seen many comments online about electric cars being heavier than ICE cars.  I was very surprised to see your numbers showing that the difference is only 10-15% of the total weight.  Since batteries improve every year, in the near future the weight difference will depend completely on the range the designers want (more range more weight).  I note that popular big SUVs and 4 door pickups are even heavier.

    I agree with you that this is trivial.   As I said in comment 4, this looks like fossil propaganda.

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