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>They're up if you compare whole system emissions for the car vs. Emissions at a ff plant. The sleight of hand is in the definition of "emissions". If you mea

>They're up if you compare whole system emissions for the car vs. Emissions at a ff plant. The sleight of hand is in the definition of "emissions". If you mean CO2 - then no, not really. If you are powering your EV with a fossil-fuel powered grid, then the transmission and battery losses make up for the small gain in power plant efficiency over an ICE (as I already said). The CO2 argument for an EV only works when the grid has a substantial "green generation" component. If you mean "emissions that are immediately bad for people" - it depends who you are talking about. EVs replace tailpipe emissions at the point of use with centralised emissions, both at the point of manufacture, and at the point of charging power generation (which will most likely be in a Western country with well-controlled emissions). As a cyclist, I have to admit it's nice not to breathe in tailpipe fumes. I try not to worry too much about all the damage being done by EV manufacture far far away from me.

Schroedingersat 4y ago
> If you mean CO2 - then no, not really. If you are powering your EV with a fossil-fuel powered grid, then the transmission and battery losses make up for the small gain in power plant efficiency over an ICE (as I already said). The CO2 argument for an EV only works when the grid has a substantial "green generation" component. EVs waste a lot less power than ICEs after the motor. Much of it not for any reason that couldn't be true of an ICE as well except for design priorities. 200Wh/km of wall socket power is about 60MJ per 100km. If that came from coal in a modern-ish plant it's about 10-15kg of CO2. From gas it's around 5-8kg. A highly efficient ICE produces 50gCO2e per km or 5kg for the same distance. This looks good until you consider that's not where the supply chain ends. Producing that petrol took another 3kg, or maybe 5kg if it was tar sands. A mostly-ff mix EV starts to look good here. But it's also not end of the line for the gas plant. Fugitive methane will double its GHG output. Coal has NOx and some deleterious effects that aren't precisely GHG but are just as bad. So the tesla produces more than the econobox. But an 'equivalent' once you game the metrics and compare against a Porsche Cayanne produces more than the tesla. Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles).
- jryhjythtr 4y ago
  >EVs waste a lot less power than ICEs after the motor. I'm talking about electrical transmission losses. The worst-case is for high-current, domestic loads, where about 15% of the power from the electrical power generator is lost. Add in another approx. 15% for charging and discharging the EV battery, and it's not so good. >200Wh/km of wall socket power is about 60MJ per 100km You forgot the above losses. >A mostly-ff mix EV starts to look good here. Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! >Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles). Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good.
  - Schroedingersat 4y ago
    > You forgot the above losses. 200Wh is about a 20% estimation-factor on top of the commonly claimed 160Wh/km for a tesla. This accounts for any losses from charger to battery. Losses past that point are irrelevant because the point of measurement is battery drain per km. Differences between the test protocol and real world should be mirrored in the econobox stats. Emissions figures were commonly quoted per kWh at the wall socket. > Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! Precisely my point? I'm asserting that a city-car econobox has better marginal per km emissions than a luxury sports EV. A cayanne will have about 4-6x the emissions as the econobox and that comparison will favour the tesla. Also please do point out where they were optimistic -- there are very few ICEs that get 50g/km? EV makers play sleight of hand by eliminating the segment of small light cars that can get you two cities over, then claiming their replacement in the form of a luxury performance car is 'better' by comparing it to luxury performance SUVs. > Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! This isn't as much as you think, most of the industry isn't using NMC anymore and there's less of the expensive materials per cell even compared to earlier LFP variants. If you're not insisting on obscene power densities and range you'll never use then 30kWh of LFP batteries has GHG impact commensurable with a few thousand km of usage of either the econobox or the coal powered luxury EV -- it doesn't take much to tip the balance. Similarly you can use motors without scarce metals. > Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good. Because EVs are here to save the car industry not the planet. Although they do have one positive externality: a bunch of people willing to pay $500-1000/kWh allowed for the development of the battery industry where doing it to reduce emissions would have never happened.

Schroedingersat 4y ago

> If you mean CO2 - then no, not really. If you are powering your EV with a fossil-fuel powered grid, then the transmission and battery losses make up for the small gain in power plant efficiency over an ICE (as I already said). The CO2 argument for an EV only works when the grid has a substantial "green generation" component. EVs waste a lot less power than ICEs after the motor. Much of it not for any reason that couldn't be true of an ICE as well except for design priorities. 200Wh/km of wall socket power is about 60MJ per 100km. If that came from coal in a modern-ish plant it's about 10-15kg of CO2. From gas it's around 5-8kg. A highly efficient ICE produces 50gCO2e per km or 5kg for the same distance. This looks good until you consider that's not where the supply chain ends. Producing that petrol took another 3kg, or maybe 5kg if it was tar sands. A mostly-ff mix EV starts to look good here. But it's also not end of the line for the gas plant. Fugitive methane will double its GHG output. Coal has NOx and some deleterious effects that aren't precisely GHG but are just as bad. So the tesla produces more than the econobox. But an 'equivalent' once you game the metrics and compare against a Porsche Cayanne produces more than the tesla. Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles).

jryhjythtr 4y ago
>EVs waste a lot less power than ICEs after the motor. I'm talking about electrical transmission losses. The worst-case is for high-current, domestic loads, where about 15% of the power from the electrical power generator is lost. Add in another approx. 15% for charging and discharging the EV battery, and it's not so good. >200Wh/km of wall socket power is about 60MJ per 100km You forgot the above losses. >A mostly-ff mix EV starts to look good here. Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! >Really to reduce emissions quickly in urban or suburban areas we need more vehicles that look like a Zev, an Aptera, suzuki samba, a golf cart or a bicycle etc. and fewer that resemble a tesla or a monster truck (as well as more rail based vehicles). Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good.
- Schroedingersat 4y ago
  > You forgot the above losses. 200Wh is about a 20% estimation-factor on top of the commonly claimed 160Wh/km for a tesla. This accounts for any losses from charger to battery. Losses past that point are irrelevant because the point of measurement is battery drain per km. Differences between the test protocol and real world should be mirrored in the econobox stats. Emissions figures were commonly quoted per kWh at the wall socket. > Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! Precisely my point? I'm asserting that a city-car econobox has better marginal per km emissions than a luxury sports EV. A cayanne will have about 4-6x the emissions as the econobox and that comparison will favour the tesla. Also please do point out where they were optimistic -- there are very few ICEs that get 50g/km? EV makers play sleight of hand by eliminating the segment of small light cars that can get you two cities over, then claiming their replacement in the form of a luxury performance car is 'better' by comparing it to luxury performance SUVs. > Not at all. By your (very optimistic) calculations, they are about the same. You'll never pay off the CO2 debt of manufacturing the EV battery, let alone start averting the climate catastrophe! This isn't as much as you think, most of the industry isn't using NMC anymore and there's less of the expensive materials per cell even compared to earlier LFP variants. If you're not insisting on obscene power densities and range you'll never use then 30kWh of LFP batteries has GHG impact commensurable with a few thousand km of usage of either the econobox or the coal powered luxury EV -- it doesn't take much to tip the balance. Similarly you can use motors without scarce metals. > Very true. Weird that all of the currently-pushed solutions involve large and expensive EVs that barely do any good. Because EVs are here to save the car industry not the planet. Although they do have one positive externality: a bunch of people willing to pay $500-1000/kWh allowed for the development of the battery industry where doing it to reduce emissions would have never happened.