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> EVs are a massive, massive improvement To be honest even this is a bit of an overstatement. An MIT study found that a huge chunk of the lifetime emissions of

by culi 4y ago

> EVs are a massive, massive improvement To be honest even this is a bit of an overstatement. An MIT study found that a huge chunk of the lifetime emissions of a vehicle is in the production alone. EVs, mostly due to their batteries, have much much higher production emissions. And given how dirty our current energy production is (and the added costs and inefficiencies of storing and transporting electricity) we won't feel the benefits of EVs offsetting the initial added costs for many many years Also given how notoriously unreliable certain brands like Tesla have been (27th of 28 in Consumer Reports reliability index) it's possible that the added maintenance costs will push this break even point even further down the road But as of right now all we've really managed to do is push these emissions from the first world (combustion emissions) to the third world (production emissions) EDIT: link to MIT study: https://energy.mit.edu/research/mobilityofthefuture/ https://energy.mit.edu/research/mobilityofthefuture/ Around 40% of an EVs lifetime emissions are from production alone. Tesla's tend to be even higher because of the larger batteries and less efficient production

nevereveragain 4y ago
> For similar-sized vehicles in the U.S. today, per-mile lifecycle (including vehicle and battery production) greenhouse gas emissions for battery electric vehicles run on the present U.S.-average grid electricity are approximately 55% of the emissions from conventional internal combustion engine vehicles. Electric vehicles have almost half the lifetime emissions. That's huge, no matter how you spin it.
- culi 4y ago
  Sure but with about 167% as many emissions from production, I'm just saying there's going to be an immediate increase in emissions. Also one thing missing from this analysis is maintenance. The three factors taken into account are initial production (much higher for EVs), cost of fuel production (also much higher for EVs), and emissions from fuel combustion (0 for EVs). However batteries don't last forever and it still remains to be seen that EVs can reach the maintenance costs of combustion engine vehicles (with Tesla being a notable argument against EVs potential)
  - Robotbeat 4y ago
    Fuel production is much cheaper for EVs, what are you talking about? The batteries last longer than the 150,000km these studies assume. My 2013 Model S is at 209,000 kilometers and going strong with little (10% or less) range reduction. I looked at the study a bit, and they use Model S-sized battery size and efficiency assumptions (about 3mi/kWh) to compare to a Camry. More appropriate would be Model 3 assumptions (4mi/kWh). The emissions factors are from a white paper 5 years ago, itself using older data. They assume 525grams of CO2 per kWh for the reference case going down to 345 in 2050, but the US already has emissions of about 375gramsCO2/kWh and falling. Just terrible assumptions. A bunch of stuff like that in the study. And it compounds! A factor of 1.33 bigger battery (3mi/kWh instead of 4mi/kWh) whose manufacturing emissions are 1.41 times as high (525grams of CO2 per kWh vs 372, if we optimistically assume electricity is the main energy input but pessimistically assume the energy needed to make a kWh of capacity remains the same) means a factor of 1.9 exaggeration in manufacturing emissions. Plus the operating emissions per mile are also exaggerated by a factor of 1.9… Finally: Batteries in modern EVs last the life of the vehicle. 500,000km or so. Potentially longer with LFP cells.
    - culi 4y ago
      > Fuel production is much cheaper for EVs, what are you talking about? No it's very much not. Please see chapter 4 of the linked MIT report: Fuel production emissions are also typically higher for BEVs (and FCEVs) because, on average, generating and delivering a megajoule of electricity or hydrogen to a vehicle battery or fuel cell consumes much more energy than producing and delivering a megajoule of gasoline to the fuel tank of an ICE
      - Robotbeat 4y ago
        But you said “cheaper,” additionally this ignores the input fossil energy of the gasoline, and it’s per joule of thermal energy, not useful mechanical energy. It’s a weird metric that isn’t very enlightening. It’s mixing low-entropy electrical energy with high-entropy thermal “primary energy.” It’s also not what you actually said. The cost of energy (as well as emissions) per mile traveled is far, FAR less in electric vehicles.
Robotbeat 4y ago
> Tesla's tend to be even higher because of the larger batteries and less efficient production This is false and actually the opposite is true. They actually used Model S sedan figures (3mi/kWh) for efficiency to compare to Camry sized vehicle. The more appropriate comparison is to a Model 3, which gets 4mi/kWh. People underestimate how efficient Tesla’s powertrains are compared to most competitors. Tesla tends to do much BETTER at efficiency than their peers, not worse.
- hedora 4y ago
  I assumed Teslas had poor fuel efficiency due to their size, but then I found this: https://evtool.ucsusa.org https://evtool.ucsusa.org The Model 3's (mid range 2020) MPGe-CO2 is a bit better than a BMW i3 (2018). The i3 is a little euro city car thing. They carefully optimized the BMW for weight, and also have some funky custom ultra efficient tires. For example, the frame is made of (hemp - supposedly lighter) fiberglass and carbon fiber, and they didn't offer power seats. It has a tiny trunk / no front trunk. It only gets EPA 135 miles per charge. The BMW and Tesla are both much better than a 2022 BMW i4, Nissan Leaf, or Polestar 2. They're a bit better than the most recent Fiat 500e, which is closer to the i3's size. Tesla's energy efficiency vs. size is really impressive.
- culi 4y ago
  I'm not talking about efficiency per mile. I'm talking about manufacturing efficiency. Tesla pulls stunts like building a giga factory in AZ for the tax breaks. It makes economic sense but does not make sense when measuring by the added emissions necessary to concentrate all those materials so far away from the rest of the supply chain loop They're also just... bad at making them. A 2020 survey by JD Power found that Tesla ranked last of the 38 brands they looked at in initial quality. It's a measurement of how many problems new vehicles face in the first 90 days of owning them This is consistent with Consumer Reports rankings of Tesla as second to last in reliability This is what I'm talking about when I say "inefficient manufacturing". Not fuel usage
hedora 4y ago
> * An MIT study found that a huge chunk of the lifetime emissions of a vehicle is in the production alone. EVs, mostly due to their batteries, have much much higher production emissions.* At this point, that's only true if you're living in the dirtiest power grid in the US, are a low milage driver, and you junk your EV within two years of purchasing it new. Also, the ICE car in this comparison has to be over a decade old (< 10% of the original embodied CO2 averaged out over the years), has to have top-tier fuel efficiency and also be much smaller than the EV. The union of concerned scientists has a calculator for this based on zip code, and the exact model of EV.

by culi 4y ago

nevereveragain 4y ago

> For similar-sized vehicles in the U.S. today, per-mile lifecycle (including vehicle and battery production) greenhouse gas emissions for battery electric vehicles run on the present U.S.-average grid electricity are approximately 55% of the emissions from conventional internal combustion engine vehicles. Electric vehicles have almost half the lifetime emissions. That's huge, no matter how you spin it.

culi 4y ago
Sure but with about 167% as many emissions from production, I'm just saying there's going to be an immediate increase in emissions. Also one thing missing from this analysis is maintenance. The three factors taken into account are initial production (much higher for EVs), cost of fuel production (also much higher for EVs), and emissions from fuel combustion (0 for EVs). However batteries don't last forever and it still remains to be seen that EVs can reach the maintenance costs of combustion engine vehicles (with Tesla being a notable argument against EVs potential)
- Robotbeat 4y ago
  Fuel production is much cheaper for EVs, what are you talking about? The batteries last longer than the 150,000km these studies assume. My 2013 Model S is at 209,000 kilometers and going strong with little (10% or less) range reduction. I looked at the study a bit, and they use Model S-sized battery size and efficiency assumptions (about 3mi/kWh) to compare to a Camry. More appropriate would be Model 3 assumptions (4mi/kWh). The emissions factors are from a white paper 5 years ago, itself using older data. They assume 525grams of CO2 per kWh for the reference case going down to 345 in 2050, but the US already has emissions of about 375gramsCO2/kWh and falling. Just terrible assumptions. A bunch of stuff like that in the study. And it compounds! A factor of 1.33 bigger battery (3mi/kWh instead of 4mi/kWh) whose manufacturing emissions are 1.41 times as high (525grams of CO2 per kWh vs 372, if we optimistically assume electricity is the main energy input but pessimistically assume the energy needed to make a kWh of capacity remains the same) means a factor of 1.9 exaggeration in manufacturing emissions. Plus the operating emissions per mile are also exaggerated by a factor of 1.9… Finally: Batteries in modern EVs last the life of the vehicle. 500,000km or so. Potentially longer with LFP cells.
  - culi 4y ago
    > Fuel production is much cheaper for EVs, what are you talking about? No it's very much not. Please see chapter 4 of the linked MIT report: Fuel production emissions are also typically higher for BEVs (and FCEVs) because, on average, generating and delivering a megajoule of electricity or hydrogen to a vehicle battery or fuel cell consumes much more energy than producing and delivering a megajoule of gasoline to the fuel tank of an ICE
    - Robotbeat 4y ago
      But you said “cheaper,” additionally this ignores the input fossil energy of the gasoline, and it’s per joule of thermal energy, not useful mechanical energy. It’s a weird metric that isn’t very enlightening. It’s mixing low-entropy electrical energy with high-entropy thermal “primary energy.” It’s also not what you actually said. The cost of energy (as well as emissions) per mile traveled is far, FAR less in electric vehicles.

Robotbeat 4y ago

> Tesla's tend to be even higher because of the larger batteries and less efficient production This is false and actually the opposite is true. They actually used Model S sedan figures (3mi/kWh) for efficiency to compare to Camry sized vehicle. The more appropriate comparison is to a Model 3, which gets 4mi/kWh. People underestimate how efficient Tesla’s powertrains are compared to most competitors. Tesla tends to do much BETTER at efficiency than their peers, not worse.

hedora 4y ago
I assumed Teslas had poor fuel efficiency due to their size, but then I found this: https://evtool.ucsusa.org https://evtool.ucsusa.org The Model 3's (mid range 2020) MPGe-CO2 is a bit better than a BMW i3 (2018). The i3 is a little euro city car thing. They carefully optimized the BMW for weight, and also have some funky custom ultra efficient tires. For example, the frame is made of (hemp - supposedly lighter) fiberglass and carbon fiber, and they didn't offer power seats. It has a tiny trunk / no front trunk. It only gets EPA 135 miles per charge. The BMW and Tesla are both much better than a 2022 BMW i4, Nissan Leaf, or Polestar 2. They're a bit better than the most recent Fiat 500e, which is closer to the i3's size. Tesla's energy efficiency vs. size is really impressive.
culi 4y ago
I'm not talking about efficiency per mile. I'm talking about manufacturing efficiency. Tesla pulls stunts like building a giga factory in AZ for the tax breaks. It makes economic sense but does not make sense when measuring by the added emissions necessary to concentrate all those materials so far away from the rest of the supply chain loop They're also just... bad at making them. A 2020 survey by JD Power found that Tesla ranked last of the 38 brands they looked at in initial quality. It's a measurement of how many problems new vehicles face in the first 90 days of owning them This is consistent with Consumer Reports rankings of Tesla as second to last in reliability This is what I'm talking about when I say "inefficient manufacturing". Not fuel usage

hedora 4y ago

> * An MIT study found that a huge chunk of the lifetime emissions of a vehicle is in the production alone. EVs, mostly due to their batteries, have much much higher production emissions.* At this point, that's only true if you're living in the dirtiest power grid in the US, are a low milage driver, and you junk your EV within two years of purchasing it new. Also, the ICE car in this comparison has to be over a decade old (< 10% of the original embodied CO2 averaged out over the years), has to have top-tier fuel efficiency and also be much smaller than the EV. The union of concerned scientists has a calculator for this based on zip code, and the exact model of EV.