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Re:A Most Peculiar Test Drive by ricardobeat on Thursday February 14, 2013 @09:39AM (#5219591)
Who in their right mind, specially someone who is reportedly a climate and energy expert, would think braking recharges the car?

edit: recharge as in having a net gain of energy. Even if you roll down a 3-mile mountain with the brakes pushed, you'd only be recovering energy spent on the way up, minus losses.

Re:A Most Peculiar Test Drive by antiterra on Thursday February 14, 2013 @10:04AM (#5219714)
Maybe he read a bit too much of Tesla's copy:

In contrast slower city driving speeds are more efficient and electric vehicles have a unique benefit in stop and go, low-speed driving due to regenerative braking

http://www.teslamotors.com/blog/model-s-efficiency-and-range

Re:A Most Peculiar Test Drive by ryen on Thursday February 14, 2013 @02:46PM (#5221660)
Since when does "efficient" mean a net-gain in energy? Seems like Broder needs to revisit his high school Science AND English classes.
Re:A Most Peculiar Test Drive by antiterra on Thursday February 14, 2013 @05:17PM (#5222825)
He simply believed that stop & go city driving would help instead of hurt his mileage. Whether that's correct or not depends on the maintained speed. Driving at. steady 75mph on a highway is quite possibly less efficient than stop and go downtown. At 55 mph, maybe not, but how is Broder supposed to know this off the top of his head if a Tesla phone rep is giving him bad info?
Re:A Most Peculiar Test Drive by msrpotus on Thursday February 14, 2013 @09:44AM (#5219621)
Anyone who has driven a similar car. Priuses do the same thing and I think other hybrids do, as well.
Re:A Most Peculiar Test Drive by olefoo on Thursday February 14, 2013 @10:08AM (#5219730)
But the second law of thermodynamics means that you can't get as much out of regenerative braking as you put in to the cars potential energy. It's not going to magically allow your car to recharge itself from braking; all it does is recapture a fraction of the energy you've spent accelerating the car or hauling it up a hill.
Re:A Most Peculiar Test Drive by mpyne on Thursday February 14, 2013 @10:30AM (#5219855)
Regenerative braking allows you to more efficiently drive within a city.

But the big win is driving at city speeds. I had explained this the other day, but power usage depends approx. on the square of your velocity.

So averaging 30mph in the city would take about 1/4 as much power as averaging 60mph on the highway, all other things being equal.

Normally all other things are not equal, as idling at a city stoplight wastes energy in a gas-powered machine, and pressing the brakes wastes energy in a gas-powered machine.

With an EV idling uses very little energy, and you can reclaim some energy from braking. Braking is still a net loss, but not as much.

Combine the two effects with a 4x power efficiency and it's not at all impossible for a hybrid to get better mileage in city, especially in stop-and-go traffic where the average speed is even lower.

Re:A Most Peculiar Test Drive by mncolinlee on Thursday February 14, 2013 @01:56PM (#5221252)
I have a friend who owns a Tesla Model S who says the regen is not as efficient in stop and go traffic as lighter vehicles. The Prius and Leaf are thousands of pounds lighter. (He still loves his car.)

He says the Tesla seems more efficient on county highways than side roads because the losses from accelerating the vehicle's over 4500 pound weight exceed losses from air resistance at those speeds.

Re:A Most Peculiar Test Drive by ricardobeat on Thursday February 14, 2013 @10:13AM (#5219758)
I meant recharge as in 'add more energy than was spent'. Braking only recovers a small amount of energy, which was already used.
Re:A Most Peculiar Test Drive by pbreit on Thursday February 14, 2013 @12:48PM (#5220681)
If you're going to make such an accusation you should be much more careful with your wording.
Re:A Most Peculiar Test Drive by alan_cx on Thursday February 14, 2013 @03:57PM (#5222213)