3 ms·

Bah, MPGe, not MPG. And anyway, MPG has been the standard of efficiency measurement for a century now, so such an argument is a bit weaselly, don't you think?

Bah, MPGe, not MPG. And anyway, MPG has been the standard of efficiency measurement for a century now, so such an argument is a bit weaselly, don't you think? My claim still stands. The Volt doesn't need three clutches, but it has three because GM is concerned about efficiency, and Tesla not as much. > Not to mention the fact that any electric car will be more energy efficient than one using an internal combustion engine. The Volt has an ICE.

aidenn0 14y ago
MPG(e) measures one aspect of efficiency: how much stored energy it takes to move the vehicle a given distance. If you use MPG, then a bus loses big time since a bus gets way lower MPG than a car. Another measure is per-passenger MPG(e) A bus now looks a whole lot better, and a full Model S with jump-seats is more efficient than a full leaf in terms of per-passenger MPGe. Another measure of efficiency is how efficient it turns the energy stored (gas, electricity, etc.) into kinetic energy. In this measure the weight of vehicle is irrelevant. The bus probably does pretty well as large diesel engines are typically more efficient than small gas engines, but pretty much all electrics will beat out all ICEs since the best ICE vehicles are a shade under 50% efficient, which is trivially beatable in an electric.
- SeanLuke 14y ago
  > Another measure is per-passenger MPG(e) A bus now looks a whole lot better, and a full Model S with jump-seats is more efficient than a full leaf in terms of per-passenger MPGe. All very true, but still very weaselly IMHO. Since the Leaf hauls five passengers, what you're really saying is that the Model S is acceptably efficient only if you're always carrying six passengers. I'm willing to bet that, assuming your Model S even has the child jump-seats in the back, this is probably well less than 10% of the use cases for the kinds of people buying this car. And of course it's true that an ICE is less efficient than an electric motor. That's not what was claimed. What was claimed was that "any electric car will be more energy efficient than one using an internal combustion engine", that is, dismissing the Volt and C-Max. I'm not saying that Tesla shouldn't have done what they did: they were very smart in developing a competitor to the BMW 7-series. The long range is smart, and the lack of an ICE backup is smart, and the high-end market is smart. It was the right decision to make. But it is nonetheless still fair to say that the Model S isn't a particularly efficient car in comparison to its electric and plug-in hybrid competition.
  - aidenn0 14y ago
    The main point was the Model S could easily be just as thermodynamically efficient as the Leaf. On a side note, I can't fit my family of 5 in a Leaf since kids have to be in a car-seat until age 8, and fitting 3 car-seats in the backseat of a Leaf is a no-go.

aidenn0 14y ago

MPG(e) measures one aspect of efficiency: how much stored energy it takes to move the vehicle a given distance. If you use MPG, then a bus loses big time since a bus gets way lower MPG than a car. Another measure is per-passenger MPG(e) A bus now looks a whole lot better, and a full Model S with jump-seats is more efficient than a full leaf in terms of per-passenger MPGe. Another measure of efficiency is how efficient it turns the energy stored (gas, electricity, etc.) into kinetic energy. In this measure the weight of vehicle is irrelevant. The bus probably does pretty well as large diesel engines are typically more efficient than small gas engines, but pretty much all electrics will beat out all ICEs since the best ICE vehicles are a shade under 50% efficient, which is trivially beatable in an electric.

SeanLuke 14y ago
> Another measure is per-passenger MPG(e) A bus now looks a whole lot better, and a full Model S with jump-seats is more efficient than a full leaf in terms of per-passenger MPGe. All very true, but still very weaselly IMHO. Since the Leaf hauls five passengers, what you're really saying is that the Model S is acceptably efficient only if you're always carrying six passengers. I'm willing to bet that, assuming your Model S even has the child jump-seats in the back, this is probably well less than 10% of the use cases for the kinds of people buying this car. And of course it's true that an ICE is less efficient than an electric motor. That's not what was claimed. What was claimed was that "any electric car will be more energy efficient than one using an internal combustion engine", that is, dismissing the Volt and C-Max. I'm not saying that Tesla shouldn't have done what they did: they were very smart in developing a competitor to the BMW 7-series. The long range is smart, and the lack of an ICE backup is smart, and the high-end market is smart. It was the right decision to make. But it is nonetheless still fair to say that the Model S isn't a particularly efficient car in comparison to its electric and plug-in hybrid competition.
- aidenn0 14y ago
  The main point was the Model S could easily be just as thermodynamically efficient as the Leaf. On a side note, I can't fit my family of 5 in a Leaf since kids have to be in a car-seat until age 8, and fitting 3 car-seats in the backseat of a Leaf is a no-go.