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The climate argument is not "weak for electric cars." Electric cars are about a factor of 2.5 better in terms of emissions per mile even with the current US ele

The climate argument is not "weak for electric cars." Electric cars are about a factor of 2.5 better in terms of emissions per mile even with the current US electric grid. A 35mpg car emits about 250 grams of carbon per mile (a gallon of gasoline emits about 20 pounds of CO2). US emissions per kWh using the most recent data is about 400-410 grams per kWh. A Model 3 gets about 4.1 miles per kWh. So each mile emits just 100 grams. And in California (which has the most EVs of any state by far), where the electricity carbon intensity is more like 200 grams per kWh, it's just 50 grams per mile in the Model 3, or about a factor of 5 better than the gasoline car.

mikemotherwell 7y ago
What percentage of emissions is usage vs manufacture? I've looked, but I can't get a figure.
- Robotbeat 7y ago
  The main difference between EVs and standard cars is the battery. Estimates of battery emissions vary widely, but reviews show an average of about 110kg of CO2 per kWh of capacity: https://theicct.org/sites/default/files/publications/EV-life-cycle-GHG_ICCT-Briefing_09022018_vF.pdf https://theicct.org/sites/default/files/publications/EV-life... (Although this is improving with time and may be as low as 56kgCO2/kWhcapacity). So a 50kWh Model 3 has about 5.5mT of emissions from its battery. The rest of it may have lower emissions than a conventional car (since there's no engine, exhaust, fuel tank, etc), but pessimistically we can just assume that the difference in manufacturing emissions between EV and standard is just the battery. Over a 175,000 mile lifetime, a 35mpg gas car will emit 45.4 tonnes of CO2. And a Model 3 (4.1kWh/mile) will emit about 8.5 tonnes with Californian electricity or 17 tonnes with US average grid electricity. In either case, the vast majority of emissions is in the actual energy to fill up the vehicle, not the battery, and electric cars are FAR better (even with a >200 mile range battery which is considered very large in much of the literature) in this respect. A factor of 3.2 times better in California (including the battery) and still a respectable factor of 2 times better in the US with current electricity mix. But of course, if you buy the EV now and it lasts 10-15 years (including secondary and tertiary owners), the US and Californian electric grid will be much better as coal (and later natural gas) is phased out.
  - crankylinuxuser 7y ago
    > But of course, if you buy the EV now and it lasts 10-15 years With companies like Tesla... they are the D-Link of vehicles. They absolutely don't want long term stable good cars. They want you at the 4-5 year mark to buy a new one. And given the company has harassed engineers poking at under the hood, they will highly likely damage your car via remote disables or other 'trickery'. I don't trust anything that Musk puts his hands on. There's a good reason for that.
    - scrumbledober 7y ago
      Any source on them not wanting long term stable good cars or is this just speculation, and if so what makes you speculate this? Other than body panel gap problems i'm unaware of any real build quality issues and apparently the motors are designed for a million miles before service.
    - Obi_Juan_Kenobi 7y ago
      All the older batteries are holding up very well, so the admittedly limited data we have directly contradicts that. I'd like to see a better right-to-repair stance taken by Tesla, but their products have thus-far proven durable. You can dislike Musk all you want, but it doesn't change reality.
    - zaroth 7y ago
      If anything it’s the other way. The software updates provide a huge boost to the existing fleet, features that you would normally have to trade-in and get a new car to enjoy. In some cases you can even upgrade the hardware (e.g. the AP and MCU) with the latest shipping parts to keep your model fresh. This is not universally true - there is some drama over a promised Model S MCU upgrade which a lot of people want only apparently only a handful of owners have gotten, but overall the approach is very refreshing.
- mikepurvis 7y ago
  In my opinion the carbon cost to manufacture is mostly relevant when you get into arguments about overall lifespan— like, can an EV get a battery change every 100k km and otherwise drive until the wheels fall off? If so, then it amortizes that initial cost to a much lower point than a gasoline car which is usually toast around the 200-300k mark. When comparing the per-distance numbers, though, the initial manufacture can be treated as a sunk cost; you would have paid it regardless of whether you bought an EV or conventional car.
  - Robotbeat 7y ago
    For the most part, long range (>200 mile) EVs have batteries that will last at least ~200,000 miles before range is reduced significantly. Figure about 1000 cycles. It's possible to do even better if you're careful with charging style (and larger batteries in the same vehicle tend to do better as their discharge and charge rates are proportionally less).
    - Gibbon1 7y ago
      I've been working off the belief that the limiting factor for a gasoline car is the engine which only lasts about 4-8000 hours before it's kaput. Electric motors and simple fix gear drivetrains should last much longer. EV's might well double the age of the average car on the road.
      - Robotbeat 7y ago
        I think they will, especially once the battery gets slightly larger and chemistry gets further refined. 1000 equivalent cycles times 300 miles of range per cycle is 300,000 miles. Takes about 20 years to get there, so for commuter vehicles, will almost certainly want to replace by then.
      - lotsofpulp 7y ago
        For places in the US that use salt on the roads (upper Midwest / northeast), vehicles suffer from corrosion before drivetrain issues in my experience. I would never buy a used car that has had lived through winters in places where roads are frequently salted.
- Gibbon1 7y ago
  The way I estimate this is just assume about 2 tons of CO2 per ton of steel[1]. Based on that it's hard to see a normal car requiring more than 5-6 tons of CO2 to produce. [1] Chemical reduction dominates everything. The energy required for forming and assembly would be much less.
  - Robotbeat 7y ago
    Some metals can undergo a bunch of reheats in processing (3D printing of metals is particularly bad) which could approach chemical reduction energy, but you're right to zeroth order (which is good enough in these conversations, IMHO). Good rule of thumb.
    - Gibbon1 7y ago
      One other point is most automobiles are now recycled. Going what one reads on the internet about 25% of the steel in cars comes from recycled steel. And 95% of cars are fed into the recycling stream when they are scraped.
NickM 7y ago
I've seen compelling arguments that driving a Model 3 actually even has lower average CO2 emissions per mile than riding a bike, since riding a bike requires eating extra calories to power it, and food has a substantial carbon footprint. Depends on the type of food you're eating, your local electricity grid, and many other factors of course. And obviously this ignores both manufacturing costs and the physical and psychological benefits to biking, so I'm not saying everyone should ditch biking, but it's an interesting comparison. https://twitter.com/Robotbeat/status/1102249291568029696 https://twitter.com/Robotbeat/status/1102249291568029696
- Robotbeat 7y ago
  That was me. :) The assumption was that if you have a particularly high emissions source of most of your calories (like virtually all meat especially ruminants or, interestingly, fresh fruit and not much grains, sugars, or oils), then biking could be worse. But it's just to point out how efficient electric cars can be and how diet can start to play a bigger role. I wasn't super serious about the comparison. :) (And e-bikes are much, much more efficient than an electric car... if they last long enough).
  - gpm 7y ago
    > (And e-bikes are much, much more efficient than an electric car... if they last long enough). Would this hold true for e-motorcycles as well, or are we really saying "slow moving vehicles are much more efficient than fast moving vehicles"?
    - Robotbeat 7y ago
      I think in this case it's small vehicles (low mass, low aerodynamic cross section) that are more efficient. Electric cars would only be marginally more efficient (~50% better) at low speeds due to rolling resistance (whose coefficient is basically constant with respect to speed) and parasitic loss from the computer, infotainment, climate control, etc. Per seat, electric cars are generally much better than electric motorcycles and about half as good as much slower e-bikes (although if ridden at the same speed, almost as good).
deleted 7y ago
[deleted]
chrisdhoover 7y ago
Im confused by the numbers cited. Gas only weighs 6 lbs per gallon. Assume a car gets 20 miles per gallon. How does a car produce 20 lbs of CO2 per mile?
- Robotbeat 7y ago
  Not 20 lbs of CO2 per mile. Most of the mass of gasoline is carbon. But most of the resultant CO2 mass is oxygen. So each gallon (6 lbs) of gasoline produces about 20 pounds of CO2. So in your example of a 20mpg car, each mile is a pound of CO2.
  - munk-a 7y ago
    This just reinforces how ridiculously unfamiliar I am with the actual working details of internal combustion engines - quite interesting.
- Obi_Juan_Kenobi 7y ago
  C weighs 12 O weighs 16 And there's two Os in a molecule of CO2, and gas is mostly a bunch of Cs. The Os come from the air. (and it's 20 pounds per gallon, not mile)
- fucking_tragedy 7y ago
  Combustion is a reaction between fuel and oxygen. Part of the weight comes from the fuel, the other part comes from oxygen in the atmosphere.
- peter303 7y ago
  Its 23 pounds of CO2 per 7 pound gallon of gasoline. Simple chemistry. A (CH2)x unit in gasoline combusts to CO2. Thats an increase from 14 atomic units to 44 atomic units by replacing H by O. Since the average internal combustion vehicle uses 500 gallons a year, that is about 6 tons of CO2.
- zaroth 7y ago
  This is a great question. I had exactly the same thought some time ago and was scratching my head where the extra mass was coming from. Short answer, it pulls oxygen from the air to make the CO2. Most of the mass of CO2 is from the O2 that came from the air, not the tank.
mc32 7y ago
A gallon of gasoline by itself only weighs ~7 pounds, but the reaction with the atmosphere’s oxygen results in ~20 lbs output.
seanwilson 7y ago
> The climate argument is not "weak for electric cars." Electric cars are about a factor of 2.5 better in terms of emissions per mile even with the current US electric grid. Isn't a large benefit also that the emissions generated by electric cars is centralised at the places producing the electricity, which makes it easier to clean up the pollution?
SmirkingRevenge 7y ago
The climate argument is not factually weak... but when it comes to actually persuading lots of people to change their ways... its just so weak. It's just a sad fact about our political reality today. And even among those who say they are concerned about climate change and the environment - it still can be very difficult to actually inspire some sort of productive urgency in them. Climate change is the most gradual disaster to ever to befall humanity and our psychology isn't built for that at all, en masse. On the other hand, when you see the air is turning black from the bumper to bumper traffic in your city, and then you notice yourself coughing, and your lungs hurting, at the same time... well that's a different situation.
- tunesmith 7y ago
  I think people just need to get good at making the argument, starting from premises. Simple deductive arguments that end up with a conclusion that people need to cut their emissions in half, spend $200/year on carbon offsets, and plant 20 trees / year. That's about right for an average US citizen, and if you show the reasoning then it's the sort of thing people can grasp and in turn share with other people.
CalRobert 7y ago
This is all true, though much of the impact of cats is in how they affect urban design patterns and result in cities where it's impractical and dangerous to walk, cycle, etc. , and huge amounts of land are lost to asphalt. I like EV's but they still encourage auto dependence and its associated ills.
- kaybe 7y ago
  Now I'm considering whether cities would be nicer if we would let cats influence their design... probably yes (more nature?), but there might be other problems.
  - CalRobert 7y ago
    It's something to explore. More sunny places to nap for everyone! But the toll on bird life would be substantial.

mikemotherwell 7y ago

What percentage of emissions is usage vs manufacture? I've looked, but I can't get a figure.

Robotbeat 7y ago
The main difference between EVs and standard cars is the battery. Estimates of battery emissions vary widely, but reviews show an average of about 110kg of CO2 per kWh of capacity: https://theicct.org/sites/default/files/publications/EV-life-cycle-GHG_ICCT-Briefing_09022018_vF.pdf https://theicct.org/sites/default/files/publications/EV-life... (Although this is improving with time and may be as low as 56kgCO2/kWhcapacity). So a 50kWh Model 3 has about 5.5mT of emissions from its battery. The rest of it may have lower emissions than a conventional car (since there's no engine, exhaust, fuel tank, etc), but pessimistically we can just assume that the difference in manufacturing emissions between EV and standard is just the battery. Over a 175,000 mile lifetime, a 35mpg gas car will emit 45.4 tonnes of CO2. And a Model 3 (4.1kWh/mile) will emit about 8.5 tonnes with Californian electricity or 17 tonnes with US average grid electricity. In either case, the vast majority of emissions is in the actual energy to fill up the vehicle, not the battery, and electric cars are FAR better (even with a >200 mile range battery which is considered very large in much of the literature) in this respect. A factor of 3.2 times better in California (including the battery) and still a respectable factor of 2 times better in the US with current electricity mix. But of course, if you buy the EV now and it lasts 10-15 years (including secondary and tertiary owners), the US and Californian electric grid will be much better as coal (and later natural gas) is phased out.
- crankylinuxuser 7y ago
  > But of course, if you buy the EV now and it lasts 10-15 years With companies like Tesla... they are the D-Link of vehicles. They absolutely don't want long term stable good cars. They want you at the 4-5 year mark to buy a new one. And given the company has harassed engineers poking at under the hood, they will highly likely damage your car via remote disables or other 'trickery'. I don't trust anything that Musk puts his hands on. There's a good reason for that.
  - scrumbledober 7y ago
    Any source on them not wanting long term stable good cars or is this just speculation, and if so what makes you speculate this? Other than body panel gap problems i'm unaware of any real build quality issues and apparently the motors are designed for a million miles before service.
  - Obi_Juan_Kenobi 7y ago
    All the older batteries are holding up very well, so the admittedly limited data we have directly contradicts that. I'd like to see a better right-to-repair stance taken by Tesla, but their products have thus-far proven durable. You can dislike Musk all you want, but it doesn't change reality.
  - zaroth 7y ago
    If anything it’s the other way. The software updates provide a huge boost to the existing fleet, features that you would normally have to trade-in and get a new car to enjoy. In some cases you can even upgrade the hardware (e.g. the AP and MCU) with the latest shipping parts to keep your model fresh. This is not universally true - there is some drama over a promised Model S MCU upgrade which a lot of people want only apparently only a handful of owners have gotten, but overall the approach is very refreshing.
mikepurvis 7y ago
In my opinion the carbon cost to manufacture is mostly relevant when you get into arguments about overall lifespan— like, can an EV get a battery change every 100k km and otherwise drive until the wheels fall off? If so, then it amortizes that initial cost to a much lower point than a gasoline car which is usually toast around the 200-300k mark. When comparing the per-distance numbers, though, the initial manufacture can be treated as a sunk cost; you would have paid it regardless of whether you bought an EV or conventional car.
- Robotbeat 7y ago
  For the most part, long range (>200 mile) EVs have batteries that will last at least ~200,000 miles before range is reduced significantly. Figure about 1000 cycles. It's possible to do even better if you're careful with charging style (and larger batteries in the same vehicle tend to do better as their discharge and charge rates are proportionally less).
  - Gibbon1 7y ago
    I've been working off the belief that the limiting factor for a gasoline car is the engine which only lasts about 4-8000 hours before it's kaput. Electric motors and simple fix gear drivetrains should last much longer. EV's might well double the age of the average car on the road.
    - Robotbeat 7y ago
      I think they will, especially once the battery gets slightly larger and chemistry gets further refined. 1000 equivalent cycles times 300 miles of range per cycle is 300,000 miles. Takes about 20 years to get there, so for commuter vehicles, will almost certainly want to replace by then.
    - lotsofpulp 7y ago
      For places in the US that use salt on the roads (upper Midwest / northeast), vehicles suffer from corrosion before drivetrain issues in my experience. I would never buy a used car that has had lived through winters in places where roads are frequently salted.
Gibbon1 7y ago
The way I estimate this is just assume about 2 tons of CO2 per ton of steel[1]. Based on that it's hard to see a normal car requiring more than 5-6 tons of CO2 to produce. [1] Chemical reduction dominates everything. The energy required for forming and assembly would be much less.
- Robotbeat 7y ago
  Some metals can undergo a bunch of reheats in processing (3D printing of metals is particularly bad) which could approach chemical reduction energy, but you're right to zeroth order (which is good enough in these conversations, IMHO). Good rule of thumb.
  - Gibbon1 7y ago
    One other point is most automobiles are now recycled. Going what one reads on the internet about 25% of the steel in cars comes from recycled steel. And 95% of cars are fed into the recycling stream when they are scraped.

NickM 7y ago

I've seen compelling arguments that driving a Model 3 actually even has lower average CO2 emissions per mile than riding a bike, since riding a bike requires eating extra calories to power it, and food has a substantial carbon footprint. Depends on the type of food you're eating, your local electricity grid, and many other factors of course. And obviously this ignores both manufacturing costs and the physical and psychological benefits to biking, so I'm not saying everyone should ditch biking, but it's an interesting comparison. https://twitter.com/Robotbeat/status/1102249291568029696 https://twitter.com/Robotbeat/status/1102249291568029696

Robotbeat 7y ago
That was me. :) The assumption was that if you have a particularly high emissions source of most of your calories (like virtually all meat especially ruminants or, interestingly, fresh fruit and not much grains, sugars, or oils), then biking could be worse. But it's just to point out how efficient electric cars can be and how diet can start to play a bigger role. I wasn't super serious about the comparison. :) (And e-bikes are much, much more efficient than an electric car... if they last long enough).
- gpm 7y ago
  > (And e-bikes are much, much more efficient than an electric car... if they last long enough). Would this hold true for e-motorcycles as well, or are we really saying "slow moving vehicles are much more efficient than fast moving vehicles"?
  - Robotbeat 7y ago
    I think in this case it's small vehicles (low mass, low aerodynamic cross section) that are more efficient. Electric cars would only be marginally more efficient (~50% better) at low speeds due to rolling resistance (whose coefficient is basically constant with respect to speed) and parasitic loss from the computer, infotainment, climate control, etc. Per seat, electric cars are generally much better than electric motorcycles and about half as good as much slower e-bikes (although if ridden at the same speed, almost as good).

deleted 7y ago

[deleted]

chrisdhoover 7y ago

Im confused by the numbers cited. Gas only weighs 6 lbs per gallon. Assume a car gets 20 miles per gallon. How does a car produce 20 lbs of CO2 per mile?

Robotbeat 7y ago
Not 20 lbs of CO2 per mile. Most of the mass of gasoline is carbon. But most of the resultant CO2 mass is oxygen. So each gallon (6 lbs) of gasoline produces about 20 pounds of CO2. So in your example of a 20mpg car, each mile is a pound of CO2.
- munk-a 7y ago
  This just reinforces how ridiculously unfamiliar I am with the actual working details of internal combustion engines - quite interesting.
Obi_Juan_Kenobi 7y ago
C weighs 12 O weighs 16 And there's two Os in a molecule of CO2, and gas is mostly a bunch of Cs. The Os come from the air. (and it's 20 pounds per gallon, not mile)
fucking_tragedy 7y ago
Combustion is a reaction between fuel and oxygen. Part of the weight comes from the fuel, the other part comes from oxygen in the atmosphere.
peter303 7y ago
Its 23 pounds of CO2 per 7 pound gallon of gasoline. Simple chemistry. A (CH2)x unit in gasoline combusts to CO2. Thats an increase from 14 atomic units to 44 atomic units by replacing H by O. Since the average internal combustion vehicle uses 500 gallons a year, that is about 6 tons of CO2.
zaroth 7y ago
This is a great question. I had exactly the same thought some time ago and was scratching my head where the extra mass was coming from. Short answer, it pulls oxygen from the air to make the CO2. Most of the mass of CO2 is from the O2 that came from the air, not the tank.

mc32 7y ago

A gallon of gasoline by itself only weighs ~7 pounds, but the reaction with the atmosphere’s oxygen results in ~20 lbs output.

seanwilson 7y ago

> The climate argument is not "weak for electric cars." Electric cars are about a factor of 2.5 better in terms of emissions per mile even with the current US electric grid. Isn't a large benefit also that the emissions generated by electric cars is centralised at the places producing the electricity, which makes it easier to clean up the pollution?

SmirkingRevenge 7y ago

The climate argument is not factually weak... but when it comes to actually persuading lots of people to change their ways... its just so weak. It's just a sad fact about our political reality today. And even among those who say they are concerned about climate change and the environment - it still can be very difficult to actually inspire some sort of productive urgency in them. Climate change is the most gradual disaster to ever to befall humanity and our psychology isn't built for that at all, en masse. On the other hand, when you see the air is turning black from the bumper to bumper traffic in your city, and then you notice yourself coughing, and your lungs hurting, at the same time... well that's a different situation.

tunesmith 7y ago
I think people just need to get good at making the argument, starting from premises. Simple deductive arguments that end up with a conclusion that people need to cut their emissions in half, spend $200/year on carbon offsets, and plant 20 trees / year. That's about right for an average US citizen, and if you show the reasoning then it's the sort of thing people can grasp and in turn share with other people.

CalRobert 7y ago

This is all true, though much of the impact of cats is in how they affect urban design patterns and result in cities where it's impractical and dangerous to walk, cycle, etc. , and huge amounts of land are lost to asphalt. I like EV's but they still encourage auto dependence and its associated ills.

kaybe 7y ago
Now I'm considering whether cities would be nicer if we would let cats influence their design... probably yes (more nature?), but there might be other problems.
- CalRobert 7y ago
  It's something to explore. More sunny places to nap for everyone! But the toll on bird life would be substantial.