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>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottle of petrol for your non SUV. This is a lot like the meme that solar is cheap - the part that's always left out: "At noon".

da768 4y ago
Of course, on the other side, there's never any pollution involved bringing fuel to the gas pump.
- thrown_22 4y ago
  Or to bring coal to the power plant.
  - deleted 4y ago
    [deleted]
Schroedingersat 4y ago
You forgot to include the other liter of fuel spent extracting, refining, and shipping the first one. Hence 2x. Also coal has double the emissions of oil per kWh so on an energy basis it's 1/4th
- thrown_22 4y ago
  Keep moving the goalposts bud. OP made a blatantly false claim. She was wrong. That's it.
  - Schroedingersat 4y ago
    Pointing out you're equivocating lifecycle emissions with tailpipe in response to an assertion about energy is just pointing out you haven't reached the goalposts even after moving them. A tesla 3 (top selling ev) uses about 170Wh/km. From a very low efficiency coal plant including transmission and charging losses (you don't get to double count discharge loss) this would be about 0.6kWh (thermal) or about 170g of CO2e. From a natgas plant it is 90g. A CX-5 (top selling car) is a bit lighter and gets about 8L/100km. This is about 1 kWh or 2kWh including drilling/refining or roughly 250g of CO2e. You could correctly argue that teslas are replacing smaller, lighter cars with bigger heavier ones, and that the smaller ones they displace have marginally lower CO2 emissions in spite of using double the energy because oil is lower CO2 than coal, but that's about as far as you can push it. If that was your argument then the solution is LEVs, transit, and bike lanes which is what the environmentalists you're straw manning want instead of most cars.
    - thrown_22 4y ago
      You're ignoring what it takes to bring the coal to the powerplant too. OP was making the point that boiler to wheels efficiency of electrics is higher than ices. It isn't when you factor in all the conversion losses. It's a really simple point that battery zealots fail to grasp.
      - Schroedingersat 4y ago
        > You're ignoring what it takes to bring the coal to the powerplant too. 908g/kWh is the mine to wall socket emissions figure I was using. Do you have a better supported one? https://insideevs.com/news/347916/tesla-model-3-epa-energy-consumption/ https://insideevs.com/news/347916/tesla-model-3-epa-energy-c... In EPA tests the tesla from the wall uses about 260Wh/km. Real world reports say range is from 80% to 110% of claimed, so we'll bump it up to 300Wh/km Our Mazda gets 8L/100km claimed (over 9 real world https://www.fuelly.com/car/mazda/cx-5 https://www.fuelly.com/car/mazda/cx-5) or 665Wh/km. A Civic is about the same real world if you wanted to compare that. If we burn that exact same gasolene (probably the most energy intensive fuel to extract) in a 58% efficient CCGT and use the 6% transmission loss of the US grid we get 330Wh. If you stop taking all of your rounding in the direction that favours the ICE you get around 240Wh for the EV vs 400Wh for the ICE. An Ioniq is slightly more efficient again. Even a fully fossil fueled grid requires less energy for the most popular EV than the most popular ICE car no matter which way you slice it. As soon as you use gas or coal or relax the assumptions where you drive the EV hard with the heater on and the ICE carefully with both on the highway you get more than double per energy input.
hgomersall 4y ago
Let's consider the numbers... A decent modern combined cycle gas turbine can achieve 60% efficiency, so let's take 50% to be conservative. Transmission losses are generally better than 15%, so that leaves a combined efficiency of 42.5%. A pessimistic charge/discharge efficiency for lithium ion would be 80% and I'd expect the charger to be 90% efficient, which gives us a total (pessimistic) efficiency of 31%. An internal combustion engine has an optimistic efficiency of about 30%. So, even if we ignore all the losses in fuel distribution for ICE cars and ignore regenerative effects in electric cars and the ability to incrementally decarbonise the grid, electric still has a slight advantage.
- Retric 4y ago
  Those are incredibly pessimistic numbers for power plants and optimistic numbers for ICE. On average 5% of the electricity transmitted and distributed in the United States is wasted your other numbers are similarly inaccurate. ICE engines are only ~30% efficient under optimal conditions, idling still consumes fuel and engines idle a lot in normal driving including coasting down a large hill, slowing down, stoplights etc. Similarly turning on and heavy acceleration etc is extremely inefficient. This is where the primary benefit comes for hybrid cars not regenerative breaking. Also, comparing gasoline to electricity ignores all the energy required to make gasoline. Oil refineries both use serious amounts of energy and release massive quantities of CO2 directly.
  - hgomersall 4y ago
    Indeed, I merely wished to bound the problem.
- thrown_22 4y ago
  You're missing the engine efficiency. Which is another ~90% efficiency process. That brings it down to be lower than an ice.

da768 4y ago

Of course, on the other side, there's never any pollution involved bringing fuel to the gas pump.

thrown_22 4y ago
Or to bring coal to the power plant.
- deleted 4y ago
  [deleted]

Schroedingersat 4y ago

You forgot to include the other liter of fuel spent extracting, refining, and shipping the first one. Hence 2x. Also coal has double the emissions of oil per kWh so on an energy basis it's 1/4th

thrown_22 4y ago
Keep moving the goalposts bud. OP made a blatantly false claim. She was wrong. That's it.
- Schroedingersat 4y ago
  Pointing out you're equivocating lifecycle emissions with tailpipe in response to an assertion about energy is just pointing out you haven't reached the goalposts even after moving them. A tesla 3 (top selling ev) uses about 170Wh/km. From a very low efficiency coal plant including transmission and charging losses (you don't get to double count discharge loss) this would be about 0.6kWh (thermal) or about 170g of CO2e. From a natgas plant it is 90g. A CX-5 (top selling car) is a bit lighter and gets about 8L/100km. This is about 1 kWh or 2kWh including drilling/refining or roughly 250g of CO2e. You could correctly argue that teslas are replacing smaller, lighter cars with bigger heavier ones, and that the smaller ones they displace have marginally lower CO2 emissions in spite of using double the energy because oil is lower CO2 than coal, but that's about as far as you can push it. If that was your argument then the solution is LEVs, transit, and bike lanes which is what the environmentalists you're straw manning want instead of most cars.
  - thrown_22 4y ago
    You're ignoring what it takes to bring the coal to the powerplant too. OP was making the point that boiler to wheels efficiency of electrics is higher than ices. It isn't when you factor in all the conversion losses. It's a really simple point that battery zealots fail to grasp.
    - Schroedingersat 4y ago
      > You're ignoring what it takes to bring the coal to the powerplant too. 908g/kWh is the mine to wall socket emissions figure I was using. Do you have a better supported one? https://insideevs.com/news/347916/tesla-model-3-epa-energy-consumption/ https://insideevs.com/news/347916/tesla-model-3-epa-energy-c... In EPA tests the tesla from the wall uses about 260Wh/km. Real world reports say range is from 80% to 110% of claimed, so we'll bump it up to 300Wh/km Our Mazda gets 8L/100km claimed (over 9 real world https://www.fuelly.com/car/mazda/cx-5 https://www.fuelly.com/car/mazda/cx-5) or 665Wh/km. A Civic is about the same real world if you wanted to compare that. If we burn that exact same gasolene (probably the most energy intensive fuel to extract) in a 58% efficient CCGT and use the 6% transmission loss of the US grid we get 330Wh. If you stop taking all of your rounding in the direction that favours the ICE you get around 240Wh for the EV vs 400Wh for the ICE. An Ioniq is slightly more efficient again. Even a fully fossil fueled grid requires less energy for the most popular EV than the most popular ICE car no matter which way you slice it. As soon as you use gas or coal or relax the assumptions where you drive the EV hard with the heater on and the ICE carefully with both on the highway you get more than double per energy input.

hgomersall 4y ago

Let's consider the numbers... A decent modern combined cycle gas turbine can achieve 60% efficiency, so let's take 50% to be conservative. Transmission losses are generally better than 15%, so that leaves a combined efficiency of 42.5%. A pessimistic charge/discharge efficiency for lithium ion would be 80% and I'd expect the charger to be 90% efficient, which gives us a total (pessimistic) efficiency of 31%. An internal combustion engine has an optimistic efficiency of about 30%. So, even if we ignore all the losses in fuel distribution for ICE cars and ignore regenerative effects in electric cars and the ability to incrementally decarbonise the grid, electric still has a slight advantage.

Retric 4y ago
Those are incredibly pessimistic numbers for power plants and optimistic numbers for ICE. On average 5% of the electricity transmitted and distributed in the United States is wasted your other numbers are similarly inaccurate. ICE engines are only ~30% efficient under optimal conditions, idling still consumes fuel and engines idle a lot in normal driving including coasting down a large hill, slowing down, stoplights etc. Similarly turning on and heavy acceleration etc is extremely inefficient. This is where the primary benefit comes for hybrid cars not regenerative breaking. Also, comparing gasoline to electricity ignores all the energy required to make gasoline. Oil refineries both use serious amounts of energy and release massive quantities of CO2 directly.
- hgomersall 4y ago
  Indeed, I merely wished to bound the problem.
thrown_22 4y ago
You're missing the engine efficiency. Which is another ~90% efficiency process. That brings it down to be lower than an ice.