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> An average US car emits about 4.6 tons of CO2-e per year. So, a Teslas extra manufacturing emissions are offset in 0.5 to 3.5 years. The average is 2 years, w

by _hypx 3y ago

> An average US car emits about 4.6 tons of CO2-e per year. So, a Teslas extra manufacturing emissions are offset in 0.5 to 3.5 years. The average is 2 years, which is in line with Tesla's claims. That's comparing an SUV/pickup (average vehicle sold today in the US) with a sedan. A comparable sedan, or even better a hybrid is closer to 2-3 tons per year (based on 1 gallon of gasoline = 8.8 kg of CO₂). Also, you have to include the CO₂ emissions of electricity production. At 0.818 lbs per kWh (US average from googling), that gives you roughly ~100 grams per mile. Or in the ballpark of 1.2 tons per year (12,000 miles per year average US driving). That's only a 0.8-1.8 ton reduction per year. Which is to say, at the high end of your calculations, and assuming the alternative is a efficient hybrid, then you're looking at ~20 year payback period. In other words, just using your numbers, but switching to an apples-to-apples comparison, and not ignoring grid emissions, the conclusion is totally different. NOTE: I'm assuming 1 ton = 1000 kg, so a metric ton.

credit_guy 3y ago
> A comparable sedan, or even better a hybrid is closer to 2-3 tons per year (based on 1 gallon of gasoline = 8.8 kg of CO₂). A non-hybrid Camry gets between 26 and 32 mpg in combined economy, according to the US government [1]. The average is about 30. The average driver in the US travels about 13500 miles per year, per the US FHWA [2]. That means about 450 galons. Times 8.8 makes 4 tons of CO2. Not 2-3. A hybrid is a completely different story. I personally think hybrids would be a much better solution towards decarbonization, but that was not what was being discussed here. [1]https://www.fueleconomy.gov/feg/bymodel/2023_Toyota_Camry.shtml https://www.fueleconomy.gov/feg/bymodel/2023_Toyota_Camry.sh...
- _hypx 3y ago
  Switching to 12,000 miles per year and 32 MPG (exactly, not ~30, the MPG system exaggerates differences for small numbers), you get 375 gallons or 3.3 tons per year. That is the driving number I used to get 1.2 tons per year for the Tesla (100 grams per mile). Also note that people who drive longer distances tend to be highway driving. MPG numbers go up even more. So even 39 MPG is realistic. So no, my claims are not wrong. People ignore hybrids because it is an inconvenient truth. They haven’t realized that cars of the future could easily reach 50-55 MPG with minimal cost. This weakens the argument against BEVs, so they ignore it. Even though this should be the default comparison given how straightforward it is to switch all new cars to hybrids.
  - credit_guy 3y ago
    Yes, people are purists. If something emits a gram of CO2, they think it's dirty, even if it saves one kilogram. For example, if we could switch overnight all passenger cars in the US to be fully electric, we'd save about 375 megatons of CO2-e [1]. Of course, we can't do that, but we could probably be able to do it in 20 years. Or 30. But if we could switch overnight all the coal power plants to run on natural gas, we'd save about 525 megatons of CO2-e [2] (the calculation is: 919 MT currently produced by coal times times 0.97/2.26 = 394 MT if we switch to gas, for a saving of 525 MT). Again, we can't switch overnight, but we can easily do it in 10 years; we are doing it, because coal is inefficient compared to gas. But how many people would think that it's more worth switching from coal to natgas than switching from gasoline cars to battery cars? [1] https://www.statista.com/statistics/1235091/us-passenger-car-ghg-emissions-by-vehicle-type/ https://www.statista.com/statistics/1235091/us-passenger-car... [2] https://www.eia.gov/tools/faqs/faq.php?id=74&t=11 https://www.eia.gov/tools/faqs/faq.php?id=74&t=11
    - _hypx 3y ago
      The real answer is neither: Switch to mass transit as much as possible, and build nuclear reactors instead of natural gas plants. This would very quickly drop CO2 emissions even further and not involve any new technologies nor huge new supply requirements. The problem with "purist" is that they're the classic example of letting the perfect defeat the good. In reality, they are anything but. They are arguably just greenwashing since their ideas don't scale.
      - credit_guy 3y ago
        I'm with you there. I'm keeping my fingers crossed for a nuclear renaissance, but it's not a guaranteed thing. Not by a mile. As for mass transit, how can you achieve that? That's a boring, but so difficult problem. If you take any mass transit from NYC you will not reach 60 miles in an hour. Most often you will not reach 40 miles in one hour. How do you fix that? And NYC is by far the most connected city in the country. What about the rest of the country? Fixing mass transportation in the US is an NP-hard problem.

by _hypx 3y ago

credit_guy 3y ago

> A comparable sedan, or even better a hybrid is closer to 2-3 tons per year (based on 1 gallon of gasoline = 8.8 kg of CO₂). A non-hybrid Camry gets between 26 and 32 mpg in combined economy, according to the US government [1]. The average is about 30. The average driver in the US travels about 13500 miles per year, per the US FHWA [2]. That means about 450 galons. Times 8.8 makes 4 tons of CO2. Not 2-3. A hybrid is a completely different story. I personally think hybrids would be a much better solution towards decarbonization, but that was not what was being discussed here. [1]https://www.fueleconomy.gov/feg/bymodel/2023_Toyota_Camry.shtml https://www.fueleconomy.gov/feg/bymodel/2023_Toyota_Camry.sh...

_hypx 3y ago
Switching to 12,000 miles per year and 32 MPG (exactly, not ~30, the MPG system exaggerates differences for small numbers), you get 375 gallons or 3.3 tons per year. That is the driving number I used to get 1.2 tons per year for the Tesla (100 grams per mile). Also note that people who drive longer distances tend to be highway driving. MPG numbers go up even more. So even 39 MPG is realistic. So no, my claims are not wrong. People ignore hybrids because it is an inconvenient truth. They haven’t realized that cars of the future could easily reach 50-55 MPG with minimal cost. This weakens the argument against BEVs, so they ignore it. Even though this should be the default comparison given how straightforward it is to switch all new cars to hybrids.
- credit_guy 3y ago
  Yes, people are purists. If something emits a gram of CO2, they think it's dirty, even if it saves one kilogram. For example, if we could switch overnight all passenger cars in the US to be fully electric, we'd save about 375 megatons of CO2-e [1]. Of course, we can't do that, but we could probably be able to do it in 20 years. Or 30. But if we could switch overnight all the coal power plants to run on natural gas, we'd save about 525 megatons of CO2-e [2] (the calculation is: 919 MT currently produced by coal times times 0.97/2.26 = 394 MT if we switch to gas, for a saving of 525 MT). Again, we can't switch overnight, but we can easily do it in 10 years; we are doing it, because coal is inefficient compared to gas. But how many people would think that it's more worth switching from coal to natgas than switching from gasoline cars to battery cars? [1] https://www.statista.com/statistics/1235091/us-passenger-car-ghg-emissions-by-vehicle-type/ https://www.statista.com/statistics/1235091/us-passenger-car... [2] https://www.eia.gov/tools/faqs/faq.php?id=74&t=11 https://www.eia.gov/tools/faqs/faq.php?id=74&t=11
  - _hypx 3y ago
    The real answer is neither: Switch to mass transit as much as possible, and build nuclear reactors instead of natural gas plants. This would very quickly drop CO2 emissions even further and not involve any new technologies nor huge new supply requirements. The problem with "purist" is that they're the classic example of letting the perfect defeat the good. In reality, they are anything but. They are arguably just greenwashing since their ideas don't scale.
    - credit_guy 3y ago
      I'm with you there. I'm keeping my fingers crossed for a nuclear renaissance, but it's not a guaranteed thing. Not by a mile. As for mass transit, how can you achieve that? That's a boring, but so difficult problem. If you take any mass transit from NYC you will not reach 60 miles in an hour. Most often you will not reach 40 miles in one hour. How do you fix that? And NYC is by far the most connected city in the country. What about the rest of the country? Fixing mass transportation in the US is an NP-hard problem.