Electric Vehicle Forums - Biggest reason to not use your brakes

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Biggest reason to not use your brakes

I read that the best hybrid systems can only recover up to 30% of the kinetic energy.

That means 70% of it is wasted.
Sure that's better than regular cars that waste 100%, but still 30% ain't that good.

This explains why Wayne Gerdes can get 60 MPG out of a non-hybrid Accord.
He avoids braking.

If you avoid getting up to a speed that you have to brake from you will save a ton of gas.
Leave a lot of space in front of you.

Re: Biggest reason to not use your brakes

One of the recommendations in all car driving FAQs is to avoid braking. However, the regenerative efficiencies of some of the larger vehicles that are coming into service has not been documented. Some of the hybrid utility and garbage trucks that have a lot of start-stop driving may achieve significantly higher efficiencies.

The key to regenerative braking efficiency is to avoid the mechanical part as well as to not have a significant velocity when starting to brake. A higher velocity means the air and rolling drag will also be slowing the vehicle down.

My favorite way to slow down is to coast UP an off-ramp from the highway. I'm gaining potential energy that I can use to accelerate on the descending cross street.

BTW, are you driving a hybrid? The non-hybrids in particular gain from brake avoidance, something the hybrid driver has less to worry about.

GOOD LUCK!
Bob Wilson

Re: Biggest reason to not use your brakes

Quote:

Originally Posted by bwilson4web (Post 119454)

...My favorite way to slow down is to coast UP an off-ramp from the highway. I'm gaining potential energy that I can use to accelerate on the descending cross street....

Recently, I was driving in the rolling Hill Country of Texas (Austin area). Found out on I35 I could largly mask a pulse and glide on my Insight by accelerating uphill, glide downhill. The speed was relatively constant.

Quote:

Originally Posted by Allen Ginsberg's parody of the Three Laws of Thermodynamics

First law: "You can't win."
Second law: "You can't break even."
Third law: "You can't quit."

Hybrids are good in they allow the ICE to be smaller for the same performance, and some kinetic energy is recovered. Kenny's point is it not even close to being recovered 100%. The driver is still often the biggest variable in fuel economy. Too few do it these days, but getting up to a moderate cruise with a minimum of both braking and heavy acceleration avoids a lot of wasted energy to start with.