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: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts 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 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 12,378 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 24 Thanked 121 Times in 103 Posts Friends: 10	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 Blue 2010 : Last tank 541.9 @ 49.48 pump (56.7 MFD) 5.54 CPM, 21 MPH, Lifetime:5442.2 miles 56.5 MPG pump. (62.22 MFD) 4.72 CPM. Summer MPG 57.4 Winter: 49.5 My 2006 SPM: Last tank 376.6 miles @38.21 pump (40.8 MFD) 7.17 cpm winter mpg 49.64 summer mpg 53.41 lifetime: 42,563.5 miles 51.5 mpg pump (52.7 mpg MFD) 5.51 cpm My 2007 Zenn total "fuel cost" $166.58 on "about" 9599.7 miles. 1.74 cents per mile (granted i plug in for free at work!!) My Plate: DUALPWR (Dual Power)

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03-25-2006, 11:56 AM	#4
DaveinOlyWA 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 12,378 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 24 Thanked 121 Times in 103 Posts Friends: 10	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: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts 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 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 12,378 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 24 Thanked 121 Times in 103 Posts Friends: 10	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