Fuel Economy & Emissions Talk about the mileage database, EPA, hypermiling, gas and driving strategy.

Biggest reason to not use your brakes

Thread Tools
 
Search this Thread
 
  #1  
Old 04-04-2007, 07:30 AM
kenny's Avatar
Ridiculously Active Enthusiast
Thread Starter
Join Date: Jun 2004
Location: So. California
Posts: 1,120
Default 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.
 
  #2  
Old 04-04-2007, 08:52 AM
bwilson4web's Avatar
Engineering first
Join Date: Oct 2005
Location: Huntsville, AL
Posts: 5,613
Default 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
 
  #3  
Old 04-04-2007, 10:41 AM
Delta Flyer's Avatar
Banned
Join Date: Apr 2005
Location: Lewisville (Dallas), Texas
Posts: 3,155
Default Re: Biggest reason to not use your brakes

Originally Posted by bwilson4web
...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.

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.
 
Related Topics
Thread
Topic Starter
Forum
Replies
Last Post
Hot_Georgia_2004
Off Topic
9
08-01-2007 05:25 PM
Shining Arcanine
Journalism & The Media
61
01-27-2007 08:17 AM
Jason
Hybrid & Related News
9
11-11-2006 04:24 PM
Delta Flyer
Journalism & The Media
1
10-12-2005 12:42 PM



Quick Reply: Biggest reason to not use your brakes


Contact Us -

  • Manage Preferences
  • Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Your Privacy Choices -

    When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

    © 2024 MH Sub I, LLC dba Internet Brands


    All times are GMT -7. The time now is 05:36 PM.