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by _ph_ 2222 days ago
Having a 2 ton car to move a 60kg person from stop light to stop light is just insane

That is solely determined by the energy required. And there is, where the electric car excels. A Tesla uses less than the equivalent of 2l of fuel for 100km or in other units achieves 120mpg. In situations you describe, it fares even better, as 60% of the kinetic energy built up is gained back when braking using the electric motors. So mass is much less a problem with electric cars than with combustion engines, which can't recuperate the kinetic energy.

3 comments

Regenerative braking is always, always less efficient than just not spending the energy in the first place to speed up.

And there are currently more fossil fuel cars on the road with regenerative braking than there are EVs ;-)

To use 60% less fuel, the car needs to havee appropriately less mass, so you are talking about 700kg for a 5 seated car with passengers. If you are talking about fossil fuel cars with regenerative breaking, you are talking about hybrids, which use their electric part for that, but their breaking power is limited compare to pure EVs by the electric engine power and the charging limits of the smaller battery.
Electrics are great for low-speed stop-and-go. They're not as good on a highway, though. 0% of the energy spent displacing air at 70mph is recovered.
They are still better than any car with a combustion engine at highway speeds. They don't recuperate while driving at constant speed of course, but still they have the greater efficiency of the electric motor vs. the combustion engine. Usually they have better aerodynamics too. But the weight doesn't play a role there, only making the cars physically smaller - less air resistance - would improve the energy consumption at highway speeds.
Yes, but weight (which is higher in electric cars) does not influence air resistance. Tesla’s btw have record low air resistance.
I don’t disagree with you but I see that as an aside. Millions of people don’t need 2.5 ton SUVs to cart themselves to and from the shops. Yes ok BEV will do it better but we have had scales for longer than we’d had batteries