Re:Winter chills limit range of the Tesla Model S electric car
by raverbashing on Sunday February 17, 2013 @04:35AM
(#5234714)
But driving at a slower speed uses less energy, so it should (theoretically) increase the range.
Of course, the energy consumed in 1h of cruise driving is less than 1h of stop/go "at the same speeds" (YMMV of course)
Re:Winter chills limit range of the Tesla Model S electric car
by lutusp on Sunday February 17, 2013 @04:39AM
(#5234726)
> But driving at a slower speed uses less energy, so it should (theoretically) increase the range.
My comment wasn't about low speeds, it was about stop-and-go driving. Driving at a steady speed is much more efficient than braking and then accelerating again.
Where is this stupid idea coming from? It's absolutely false -- regenerative braking can only reduce losses caused by braking, it doesn't extend the range of the car compared to driving at a steady speed. Don't expect to gain anything by choosing stop-and-go driving over steady-speed driving -- it doesn't work that way.
According to technical estimates, regenerative braking only recovers 20% of the energy otherwise lost in reducing the car's speed, but gaining that speed back requires ... wait for it -- 100% of the car's kinetic energy from the battery. Regenerative braking is better than turning all the car's kinetic energy into heat, but it has no advantage over maintaining a steady speed.
I wish this myth would go away, preferably by some education in physics.