Hacker News new | ask | show | jobs
by fspeech 2415 days ago
Your argument is incorrect as pointed out by dropin685 earlier. Additional weight by itself does not waste energy. It does require more power to accelerate. The extra power is turned into higher kinetic energy for the same cruising speed. However kinetic energy is not waste. It can be recovered during deacceleration. It's the lack of regeneration that causes ICE powered vehicles to waste energy, which doesn't apply to EVs with regeneration capabilities.
2 comments

I am obviously failing to communicate as this was meant to be about the effects of weight and traction, and how batteries are not unique for adding weight to a vehicle (other than a lower center of gravity, but that has nothing to do with my original point).

While regenerative braking is most common in electric vehicles, this also is not unique to electric vehicles. A hybrid vehicle can just as easily benefit from this, such as the Prius.

> Additional weight by itself does not waste energy. It does require more power to accelerate. The extra power is turned into higher kinetic energy for the same cruising speed. However kinetic energy is not waste. It can be recovered during deacceleration.

This is incorrect unless the engine/motor, drivetrain, and tires are all 100% efficient - additional weight always wastes energy.

But I agree with you, electric vehicles are more energy efficient than gasoline vehicles.

> A hybrid vehicle can just as easily benefit from this, such as the Prius.

If you momentarily ignore the fact that its ultimate energy source is gasoline and focus only on the regen system a hybrid is an electric vehicle, just one that (sadly) lacks a plug.

> It's the lack of regeneration that causes ICE powered vehicles to waste energy,

Not just the lack of regen. ICEs waste energy while idling, as heat, noise, and vibration, and mechanical couplings like clutches and especially fluid couplings in automatic transmissions also waste energy. Automatic transmissions in particular are only 90% mechanically efficient, on top of all the losses from the ICE.