3 ms·

Hills shouldn't make much of a difference. The car has regenerative braking so hilly or flat, it should have similar range.

jakswa 6y ago
I don't think regen braking is perfect (70% efficient maybe?). And if the battery is full, regen braking is disabled/lessened.
- gsnedders 6y ago
  Even with 100% efficiency of the powertrain you'll end up with less charge than you started with. Yes, with 100% you get the energy used to overcome gravity back, but you still have frictional (tyres have friction!) and aerodynamic (we have an atmosphere!) losses that need to be accounted for both uphill and downhill. But yes, powertrain loses exacerbate the power consumption.
  - eloisant 6y ago
    The question is whether flat or hill makes a difference. Surely friction and aerodynamic would be the same? Also: friction of tyres don't make you consume energy, it's what makes the car move actually (with no tire friction you won't move at all). The friction that makes you consume energy is within the wheels, gears, etc that are supposed to slide, also the deformation of tires makes you consume energy (which is why consumption is higher with under-inflated tires).
    - pengaru 6y ago
      There's wasteful forms of friction at the road:tire interface when steering, look up slip angles. And there's always wasteful friction at the road:tire interface due to factors like toe and camber, even when going straight. The tire's not a perfect cylinder in isolation rolling perfectly straight down a perfectly flat surface, automobiles are not single-track vehicles. Since we're already in pedantic land, tires aren't spinning in a vacuum, there's friction between the spinning tires and the air around them.
pengaru 6y ago
I wouldn't be surprised by a ~10% loss in range, which could be enough to make the EPA numbers look bogus to some drivers. Presumably there's also a subjective element, like if the driver tends to tailgate and brake late, which isn't exactly uncommon. You're not recovering any energy put into heating the brake rotors. There are also plenty of locales where you're repeatedly braking heavily for hairpin turns like winding roads on the side of a mountain. Teslas aren't exactly light vehicles...
r00fus 6y ago
Disagree strongly. Hills most definitely impact mpg/mpge. If you're going near speed limit (due to flow of traffic) then your regen isn't going to recapture as much as if you let it coast.

jakswa 6y ago

I don't think regen braking is perfect (70% efficient maybe?). And if the battery is full, regen braking is disabled/lessened.

gsnedders 6y ago
Even with 100% efficiency of the powertrain you'll end up with less charge than you started with. Yes, with 100% you get the energy used to overcome gravity back, but you still have frictional (tyres have friction!) and aerodynamic (we have an atmosphere!) losses that need to be accounted for both uphill and downhill. But yes, powertrain loses exacerbate the power consumption.
- eloisant 6y ago
  The question is whether flat or hill makes a difference. Surely friction and aerodynamic would be the same? Also: friction of tyres don't make you consume energy, it's what makes the car move actually (with no tire friction you won't move at all). The friction that makes you consume energy is within the wheels, gears, etc that are supposed to slide, also the deformation of tires makes you consume energy (which is why consumption is higher with under-inflated tires).
  - pengaru 6y ago
    There's wasteful forms of friction at the road:tire interface when steering, look up slip angles. And there's always wasteful friction at the road:tire interface due to factors like toe and camber, even when going straight. The tire's not a perfect cylinder in isolation rolling perfectly straight down a perfectly flat surface, automobiles are not single-track vehicles. Since we're already in pedantic land, tires aren't spinning in a vacuum, there's friction between the spinning tires and the air around them.

pengaru 6y ago

I wouldn't be surprised by a ~10% loss in range, which could be enough to make the EPA numbers look bogus to some drivers. Presumably there's also a subjective element, like if the driver tends to tailgate and brake late, which isn't exactly uncommon. You're not recovering any energy put into heating the brake rotors. There are also plenty of locales where you're repeatedly braking heavily for hairpin turns like winding roads on the side of a mountain. Teslas aren't exactly light vehicles...

r00fus 6y ago

Disagree strongly. Hills most definitely impact mpg/mpge. If you're going near speed limit (due to flow of traffic) then your regen isn't going to recapture as much as if you let it coast.