Coasting VS Braking

efrench515 · 03-25-2006, 10:31 AM

I have been experimenting with which provides more regenerative power. I have tried coasting for a block or two or more to get to a stop and I have tried driving as normal and applying the brakes as necessary and consistantly to come to a safe stop. I have noticed little to no difference between the two options. So my question for all the experts is Does the amout of regeneration increase as the amount of braking force is increased? I know there is a limit to the rate at which the batteries will accept a charge, It is just that I suspect inorder to provide a stronger electro-magnetic braking you would generate more electricty (at least that is what my Electrical Engineering classes in College tought me)

DaveinOlyWA · 03-25-2006, 10:42 AM

sooner you start coasting, the sooner you stop burning gas which is much more important.

now this "driving as usual" statement is difficult to quantify.

realize that regen is much greater when braking than when coasting. depending on SOC, speed and other things im sure, coasting will give back 10-20 amps. even very light braking will give back double that easily with moderate braking adding another factor close to 2 higher.

but if you are:

1)burning gas while "driving normally"

2)using your stored charge,

3) are not holding anyone up by coasting...keep in mind, if coming up to a red light that you know is still gonna either be red or have cars waiting to move, then you ARE NEVER HOLDING ANYONE UP

then you need to be coasting sooner.

iow, your goal is to NEVER touch your brakes. obviously that is very hard to do. but that is still what you want to strive to do.

darelldd · 03-25-2006, 11:47 AM

Quote:

Originally posted by DaveinOlyWA@Mar 25 2006, 07:42 AM
iow, your goal is to NEVER touch your brakes. obviously that is very hard to do. but that is still what you want to strive to do.

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In fact... along this same line of advice - you should avoid ANYTHING that slows you down as much as possible. That includes regen. If you MUST slow, then regen is a happy way to do it.

DaveinOlyWA · 03-25-2006, 11:56 AM

yup, in fact, the real objective is to anticipate congestion, moderate your speed, and be just rolling up to the intersection as the last car is pulling away from the light...

i cant even begin to tell how i feel when i nail it perfectly. the heavier the traffic, the better the feeling!@!

efrench515 · 03-25-2006, 03:34 PM

Dave and Darell,

I had noticed an increased MPG with increased coasting and I do strive to not use my brakes, and there is not much that is more fun than tryng to coast off the freway exit ram merge into traffic and make it the 1/4 mile to my first turn without hitting either the gas or the brake. Thank you for confirming my theory that braking does provide an increased amprage for recharge. It is funny i looked at my rotors the other day and they still have the original turning marks on them from the factory. True I have only driven 703 miles but must vehicles would have lost them in the first 100. Now if I can just get some warm weather so I can start getting some respectable milage.

DaveinOlyWA · 03-25-2006, 04:21 PM

wtg efrench!!

to give you an idea how much i use my brakes. granted a light touch will be regen, but my front rotors are rusted. keep your rusted and your milege will soar.

as long as you anticipate, you will have no problems doing that

03-25-2006, 10:31 AM	#1
efrench515 Member Join Date: Mar 2006 Location: Saginaw, Michigan Posts: 53 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I have been experimenting with which provides more regenerative power. I have tried coasting for a block or two or more to get to a stop and I have tried driving as normal and applying the brakes as necessary and consistantly to come to a safe stop. I have noticed little to no difference between the two options. So my question for all the experts is Does the amout of regeneration increase as the amount of braking force is increased? I know there is a limit to the rate at which the batteries will accept a charge, It is just that I suspect inorder to provide a stronger electro-magnetic braking you would generate more electricty (at least that is what my Electrical Engineering classes in College tought me) __________________ 2006 Barcelona Red Headlight flasher EV Mod

03-25-2006, 10:42 AM	#2
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,633 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	sooner you start coasting, the sooner you stop burning gas which is much more important. now this "driving as usual" statement is difficult to quantify. realize that regen is much greater when braking than when coasting. depending on SOC, speed and other things im sure, coasting will give back 10-20 amps. even very light braking will give back double that easily with moderate braking adding another factor close to 2 higher. but if you are: 1)burning gas while "driving normally" 2)using your stored charge, 3) are not holding anyone up by coasting...keep in mind, if coming up to a red light that you know is still gonna either be red or have cars waiting to move, then you ARE NEVER HOLDING ANYONE UP then you need to be coasting sooner. iow, your goal is to NEVER touch your brakes. obviously that is very hard to do. but that is still what you want to strive to do. __________________ My 2006: Last tank 463.1 miles @49.2 pump (49.4 computer) 4.22 cpm winter mpg 50.70 summer mpg 54.59 lifetime: 33,038.3 miles 52.79 mpg pump (54.04 mpg computer) 5.74 cpm My 2007 Zenn Driven 5945 miles, 2.01 cpm/ 105 mpg (at $2.05/gal), 4.04 miles/ Kwh Savings over my Prius $302.66 The Corolla...573.26 The REAL SAVINGS from not driving Corolla 657.39 +Prius= 958.18 (excludes maintenance costs...would be unfair to ICE vehicles) My Plate: DUALPWR (Dual Power)

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03-25-2006, 11:56 AM	#4
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,633 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	yup, in fact, the real objective is to anticipate congestion, moderate your speed, and be just rolling up to the intersection as the last car is pulling away from the light... i cant even begin to tell how i feel when i nail it perfectly. the heavier the traffic, the better the feeling!@!

03-25-2006, 03:34 PM	#5
efrench515 Member Join Date: Mar 2006 Location: Saginaw, Michigan Posts: 53 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Dave and Darell, I had noticed an increased MPG with increased coasting and I do strive to not use my brakes, and there is not much that is more fun than tryng to coast off the freway exit ram merge into traffic and make it the 1/4 mile to my first turn without hitting either the gas or the brake. Thank you for confirming my theory that braking does provide an increased amprage for recharge. It is funny i looked at my rotors the other day and they still have the original turning marks on them from the factory. True I have only driven 703 miles but must vehicles would have lost them in the first 100. Now if I can just get some warm weather so I can start getting some respectable milage.

03-25-2006, 04:21 PM	#6
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,633 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	wtg efrench!! to give you an idea how much i use my brakes. granted a light touch will be regen, but my front rotors are rusted. keep your rusted and your milege will soar. as long as you anticipate, you will have no problems doing that