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I find the electric car argument not entirely true due to the efficiencies of the electric motor. Producing the power in a plant and then using it on an electri

I find the electric car argument not entirely true due to the efficiencies of the electric motor. Producing the power in a plant and then using it on an electric motor is way more efficient than producing the power at the source in an ICE.

sidewndr46 3y ago
No, that isn't how it works at all. You're just measuring it a different point. Power plants have similar thermal efficiency that is compounded by the losses in transmission & charging the battery.
- mmanfrin 3y ago
  > losses in transmission & charging the battery Significantly more losses in the manufacturing, refining, delivering, and distribution of gas.
- outworlder 3y ago
  That's exactly how it works. Power plants are not even using the same cycle, it's brayton vs carnot. And power plants have a much higher efficiency overall, often two or more times higher than ICE engines. https://www.forbes.com/sites/enriquedans/2018/08/19/myths-and-shibboleths-about-electric-vehicles-the-long-tailpipe-theory/?sh=2059ba047f26 https://www.forbes.com/sites/enriquedans/2018/08/19/myths-an...
- Veserv 3y ago
  Can you provide numbers for each of those? ICE thermal efficiency vs Combined Cycle Gas Turbine efficiency, transmission losses per 100 km and expected total, battery roundtrip efficiency, electric motor efficiency?
  - sidewndr46 3y ago
    No, because it's irrelevant. Talking about "electric motor efficiency" is as pointless as talking about the efficiency of the ring and pinion in the axle of vehicle. It isn't where energy is lost. The total system efficiency is what matters. As other posters mentioned, even diesels beat the efficiency of an EV when you measure well to wheel: https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstract https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstra...
- sn0wf1re 3y ago
  Huh. Today I learned. https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstract https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstra... I always thought the difference was larger for a coal powered electric vehicle.
- alex_young 3y ago
  Even if the grid were entirely fueled by coal, 31% less energy would be needed to charge EVs than to fuel gasoline cars. If EVs were charged by natural gas, the total energy demand for highway transportation would fall by nearly half. Add in hydropower or other renewables, and the result gets even better, saving up to three-fourths of the energy currently used by gasoline-powered vehicles. https://yaleclimateconnections.org/2022/08/electrifying-transportation-reduces-emissions-and-saves-massive-amounts-of-energy/ https://yaleclimateconnections.org/2022/08/electrifying-tran...
- MagnumOpus 3y ago
  Untrue. Power plants can be 50-60% efficient (and up to 90% if the waste heat is used for district heating). Meanwhile car ICEs are at best 25-30% efficient (slightly more for diesels). Even with transmission losses of 4-6% and electric car charging/discharging losses of 10-20% the EV comes out ahead even when fired with fossil fuels and saddled with 500 pounds of extra weight.
sottol 3y ago
Also, producing gasoline is not "free". It takes energy to produce and deliver that gasoline to your car. Numbers I've seen are 5 ~ 8kWh, that's 20-30 miles of electric driving. Depending on your gasoline car's efficiency and exact kWh number above, the energy to even produce and deliver the gasoline is higher than actually driving an electric vehicle.
vkou 3y ago
Yes, but if we're going to be talking about all-in efficiency, note that a bus or train is significantly more efficient[1] than a single-person vehicle idling in gridlock. [1] In time, energy, money, infrastructure, maintenance, insurance, human health and life lost to accidents and pollution.
- bryanlarsen 3y ago
  Electric cars don't idle in gridlock, the motors don't consume energy while stopped. They are also more efficient at 10mph than they are at 50mph, let alone 70mph.
  - vkou 3y ago
    > Electric cars don't idle in gridlock No, but the humans in them do. Traffic and gridlock waste our time because cars are an incredibly inefficient way to transport people[1]. --- [1] https://humantransit.org/2012/09/the-photo-that-explains-almost-everything.html https://humantransit.org/2012/09/the-photo-that-explains-alm...

sidewndr46 3y ago

No, that isn't how it works at all. You're just measuring it a different point. Power plants have similar thermal efficiency that is compounded by the losses in transmission & charging the battery.

mmanfrin 3y ago
> losses in transmission & charging the battery Significantly more losses in the manufacturing, refining, delivering, and distribution of gas.
outworlder 3y ago
That's exactly how it works. Power plants are not even using the same cycle, it's brayton vs carnot. And power plants have a much higher efficiency overall, often two or more times higher than ICE engines. https://www.forbes.com/sites/enriquedans/2018/08/19/myths-and-shibboleths-about-electric-vehicles-the-long-tailpipe-theory/?sh=2059ba047f26 https://www.forbes.com/sites/enriquedans/2018/08/19/myths-an...
Veserv 3y ago
Can you provide numbers for each of those? ICE thermal efficiency vs Combined Cycle Gas Turbine efficiency, transmission losses per 100 km and expected total, battery roundtrip efficiency, electric motor efficiency?
- sidewndr46 3y ago
  No, because it's irrelevant. Talking about "electric motor efficiency" is as pointless as talking about the efficiency of the ring and pinion in the axle of vehicle. It isn't where energy is lost. The total system efficiency is what matters. As other posters mentioned, even diesels beat the efficiency of an EV when you measure well to wheel: https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstract https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstra...
sn0wf1re 3y ago
Huh. Today I learned. https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstract https://ui.adsabs.harvard.edu/abs/2020SJRUE..24..669A/abstra... I always thought the difference was larger for a coal powered electric vehicle.
alex_young 3y ago
Even if the grid were entirely fueled by coal, 31% less energy would be needed to charge EVs than to fuel gasoline cars. If EVs were charged by natural gas, the total energy demand for highway transportation would fall by nearly half. Add in hydropower or other renewables, and the result gets even better, saving up to three-fourths of the energy currently used by gasoline-powered vehicles. https://yaleclimateconnections.org/2022/08/electrifying-transportation-reduces-emissions-and-saves-massive-amounts-of-energy/ https://yaleclimateconnections.org/2022/08/electrifying-tran...
MagnumOpus 3y ago
Untrue. Power plants can be 50-60% efficient (and up to 90% if the waste heat is used for district heating). Meanwhile car ICEs are at best 25-30% efficient (slightly more for diesels). Even with transmission losses of 4-6% and electric car charging/discharging losses of 10-20% the EV comes out ahead even when fired with fossil fuels and saddled with 500 pounds of extra weight.

sottol 3y ago

Also, producing gasoline is not "free". It takes energy to produce and deliver that gasoline to your car. Numbers I've seen are 5 ~ 8kWh, that's 20-30 miles of electric driving. Depending on your gasoline car's efficiency and exact kWh number above, the energy to even produce and deliver the gasoline is higher than actually driving an electric vehicle.

vkou 3y ago

Yes, but if we're going to be talking about all-in efficiency, note that a bus or train is significantly more efficient[1] than a single-person vehicle idling in gridlock. [1] In time, energy, money, infrastructure, maintenance, insurance, human health and life lost to accidents and pollution.

bryanlarsen 3y ago
Electric cars don't idle in gridlock, the motors don't consume energy while stopped. They are also more efficient at 10mph than they are at 50mph, let alone 70mph.
- vkou 3y ago
  > Electric cars don't idle in gridlock No, but the humans in them do. Traffic and gridlock waste our time because cars are an incredibly inefficient way to transport people[1]. --- [1] https://humantransit.org/2012/09/the-photo-that-explains-almost-everything.html https://humantransit.org/2012/09/the-photo-that-explains-alm...