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> given things like transmission losses, etc I was completely confused for several moments there because I was thinking of automotive transmissions (which caus

> given things like transmission losses, etc I was completely confused for several moments there because I was thinking of automotive transmissions (which cause efficiency losses in regular cars but aren't used in (the vast majority of) EVs), then I realized you meant electric/infrastructural transmission losses. Right.

deleted 3y ago
[deleted]
sliken 3y ago
EVs, except in rare cases have differentials. Some even have different gears, but not Teslas. Typically EVs have 1 or 2 differentials. Granted that's less than my subaru (with 3), but still an issue.
- brucethemoose2 3y ago
  Hub motors seem so logical until the unsprung weight realization hits you. Maybe we can go back to them when EVs get lighter... Or maybe when we get superconducting motors.
  - ComputerGuru 3y ago
    I posted this elsewhere, but sharing here too: This link has an absolutely terrific comparison of tradeoffs involved in lowering vehicle weight, compares ICE to EV weight profiles, and puts the current price per kg of weight saved for ICE vehicles at $5/kg while forecasting that EVs will reach price parity on that metric by 2030. https://www.lightmetalage.com/news/industry-news/automotive/electric-vehicle-material-selection-for-chassis-and-suspension-components/ https://www.lightmetalage.com/news/industry-news/automotive/...
- ComputerGuru 3y ago
  I know the Roadster and the Taycan have trannies/gears. Don’t know of any others, though. But I didn’t say EVs don’t have diffs, it’s just that automatic transmission losses are on top of differential losses (and were pretty bad before the modern era of much better ZF and similar/knockoff designs?). Edit: this link answered my questions on drivetrain power losses: https://www.motortrend.com/how-to/modp-1005-drivetrain-power-loss/ https://www.motortrend.com/how-to/modp-1005-drivetrain-power...
  - sliken 3y ago
    I was tracking various exotic transmissions, ZF, dual clutch, various tech to give performance tweaks like rev matching and instant shifts. However fairly boring automatics got so good that they started showing better acceleration and efficiency numbers. Some designs that were dual clutch switched back to a normal clutch to save on cost, weight, and met or beat the performance of the older designs.
    - ComputerGuru 3y ago
      Yeah, I know what you mean. We live in amazing but somehow less exciting times.

deleted 3y ago

[deleted]

sliken 3y ago

EVs, except in rare cases have differentials. Some even have different gears, but not Teslas. Typically EVs have 1 or 2 differentials. Granted that's less than my subaru (with 3), but still an issue.

brucethemoose2 3y ago
Hub motors seem so logical until the unsprung weight realization hits you. Maybe we can go back to them when EVs get lighter... Or maybe when we get superconducting motors.
- ComputerGuru 3y ago
  I posted this elsewhere, but sharing here too: This link has an absolutely terrific comparison of tradeoffs involved in lowering vehicle weight, compares ICE to EV weight profiles, and puts the current price per kg of weight saved for ICE vehicles at $5/kg while forecasting that EVs will reach price parity on that metric by 2030. https://www.lightmetalage.com/news/industry-news/automotive/electric-vehicle-material-selection-for-chassis-and-suspension-components/ https://www.lightmetalage.com/news/industry-news/automotive/...
ComputerGuru 3y ago
I know the Roadster and the Taycan have trannies/gears. Don’t know of any others, though. But I didn’t say EVs don’t have diffs, it’s just that automatic transmission losses are on top of differential losses (and were pretty bad before the modern era of much better ZF and similar/knockoff designs?). Edit: this link answered my questions on drivetrain power losses: https://www.motortrend.com/how-to/modp-1005-drivetrain-power-loss/ https://www.motortrend.com/how-to/modp-1005-drivetrain-power...
- sliken 3y ago
  I was tracking various exotic transmissions, ZF, dual clutch, various tech to give performance tweaks like rev matching and instant shifts. However fairly boring automatics got so good that they started showing better acceleration and efficiency numbers. Some designs that were dual clutch switched back to a normal clutch to save on cost, weight, and met or beat the performance of the older designs.
  - ComputerGuru 3y ago
    Yeah, I know what you mean. We live in amazing but somehow less exciting times.