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NimbleYarisOwner
08-21-2007, 05:47 PM
Really thats where u loose allot of energy.

If you have a Manual you can brake by shifting into gear
which will turn the engine and the serpentine belt.

Has anybody considered taking the AC compressor and completey
making it serve a different purpose. It would compress air into a chamber.
During acceleration from a stop, you would run the aircompressor in reverse.
I dont think an AC compressor can run in reverse can it?

I never use the ACcompressor anyway for its intended function.

Or take the AC compressor out, install an electric generator which will charge a battery when activated by the brake pedal, and act as a motor during acceleration from standstill.

Thirty-Nine
08-21-2007, 05:59 PM
If you're really that intersted in modifying the AC, I'd simply unhook it so it taxes the engine less, and then remove the compressor for a weight savings.

NimbleYarisOwner
08-21-2007, 06:06 PM
What do u mean unplugging the the AC?, doesn't that AC engage with somekind electrically activated clutch when u press the AC button.

Thirty-Nine
08-21-2007, 06:33 PM
Well, the AC is run off of the engine using an accessory belt. By disconneting the belt, you are now rendering the AC useless. No belt -- no means for the compressor to turn -- less drag on the engine. Remove the 15 lb. (if that) compressor from the car. Frankly, I bet you wouldn't see a measureable increase in fuel economy, though. It's probably not worth it.

NimbleYarisOwner
08-22-2007, 09:32 AM
Does the yaris have one belt running all acceseries, i.e. a serpentine belt?
OK you have answered the question, its an accesory belt.

I am very eager to take a hacksaw to this Yaris.

YarisTom73
08-22-2007, 10:47 AM
I am very eager to take a hacksaw to this Yaris.

Can't say that I follow the logic there, my friend :confused:

Sounds eerily like something from a B horror flick :laugh:

NimbleYarisOwner
08-22-2007, 06:18 PM
Assuming you have a manual transmission,
you could use somekind of energy capture device to store braking energy.
during decel, you leave it in gear longer.

this may be possible with an airmotor.
During braking you activate a valve which controls an air motor turning it into a compressor. During accel, it runs as a motor.
An air motor attached to the engine via a belt is used to compress air into a tank. the air motor would need some kind of clutch to engage/disengage with the engine.

During accel the air motor is run in reverse to add torque to the engine.
No electricals involved accept for maybe the clutch.

whats wrong with that logic, besides crazy.

punch
08-22-2007, 07:25 PM
Really thats where u loose allot of energy.

If you have a Manual you can brake by shifting into gear
which will turn the engine and the serpentine belt.

Has anybody considered taking the AC compressor and completey
making it serve a different purpose. It would compress air into a chamber.
During acceleration from a stop, you would run the aircompressor in reverse.
I dont think an AC compressor can run in reverse can it?

I never use the ACcompressor anyway for its intended function.

Or take the AC compressor out, install an electric generator which will charge a battery when activated by the brake pedal, and act as a motor during acceleration from standstill.


maybe could've saved a $1000 by not getting a/c in the first place...

Astroman
08-22-2007, 07:38 PM
In the US, air conditioning is standard. I don't think you can get a Yaris here that doesn't have it, unless you import it from Canada.

flagmunkey
08-25-2007, 03:26 AM
so you're talkin about using the AC to compress air when braking then expelling it when accelerating?

sounds like a feat! id recommend trying it, but where woul dyou store the compressed air..

i remember reading that this type of "hybrid" was much more sustainable than a battery electric hybrid because it doesnt have as much embodied energy, and its more efficient.

NimbleYarisOwner
08-28-2007, 04:36 PM
The problem is i don't think the AC compressor can be run in reverse, but I might be wrong. Other problem is that i am not idpendently wealthy to by an extra ACcompressor from toyota to start messing with it/ figuring it out. Storring the compressed air is the easy part, I would just get 5 gallon tank, preferably aluminum to keep the weight down. There are allot of engineering variables to think about.
1) closed system, running Nitrogen? (removes water problem)
2) Cluching AC compressor in and out
3) compressing air is not the most effieicent process, from a Thermodynamic point of view but its probably the most reliable.

I cant understand why this type of idea hasn't gone any further at detroit or anywhere else? whats wrong with it?
Anyway the sloths in Detroit should be thinking about this, not me. I like air cause its clean and doesn't leave a mess.
I wonder how much an extra AC compressor costs anyway.
My other problem is I would need to get a decent CAD model of the underhood layout of the YARIS.

BailOut
08-28-2007, 07:09 PM
Storing air isn't linear. The more air you put into the tank the harder it is to get the air in the tank due to rising pressure. The more air you take out the harder it is to get out due to dropping pressure.

Storing electricity in batteries is much more linear.

swng
08-28-2007, 09:28 PM
How about a flywheel instead of pressurized air? Please see Post #8 here:http://www.yarisworld.com/forums/showthread.php?t=995&highlight=hybrid+flywheel

CF-Shane
08-28-2007, 09:48 PM
Coming from the minitruck world, there are a lot of off the shelf engine-driven-compressor solutions that could be valved to do the trick. However, I honestly don't know how much of a difference this will make (if any). I think the last couple of posts are a little bit more on the bead as to what's practical and not as lossy. Using a compressed air based solution, you will probably lose a lot of your energy to heat.

WRBlue
08-29-2007, 12:18 PM
Remove the 15 lb. (if that) compressor from the car. Frankly, I bet you wouldn't see a measureable increase in fuel economy, though. It's probably not worth it.

An A/C system weighs far more than 15lbs. The compressor alone usually weighs 30-40lbs (on all the cars I've pulled them from - Nissans, Toyotas, and Mitsubishis). Theres alot more to the system than the compressor - dryer, lines, condenser, etc. All that together usually weighs close to 75lbs.

Thirty-Nine
08-29-2007, 02:59 PM
Okay, so it weighs more. I'm still not sure I understand where we're going with this thread. Making the Yaris run on compressed air? I can tell you than an A/C compressor does not put out a lot of CFM compared to a stand-alone compressor -- in fact, not anywhere near the same volume.

Tata Motors from India has recently come up with a car powered by air. It requires a lot of pressure and needs the tanks filled after so many miles.

NimbleYarisOwner
08-29-2007, 03:35 PM
its not running all the time on compressed air, just helping to accelerate from standstill. The idea of a car running only compressed air does not make allot of sense.
I want something a home mechanic can do that will be fun to experiment with. Hey if i can get up to 40mpgavg instead of 35mpg avg then its worth it.

I like the idea of a hydraulic system, which would eliminate the inefficiencies of an air system. (hydraulic regerative braking systems are being worked on for trucks, i read in an article). The AC compressor would be perfect cause its right there already installed. If you could run it backwords it could work, but it probably can't be run in reverse.- so you would need to install a hydraulic motor. You would also need an bladder or spring accumulator to store the high pressure fluid and some valving.
I gota get out my refrigeration manual to see what psis refrigerent
compressors run at. and the horse power ratings.

ROCKLAND TOYOTA
08-29-2007, 05:10 PM
FUNNY that i saw this cause i just came back from my highlander hybrid class and i learned about regenerative braking.....

Yaris Revenge
08-30-2007, 02:45 PM
Okay, wait, I'm lost....

Let's assume that somehow you DID get the compressor to run backwards.

How is that supposed to help anything? And how the heck does it tie into the braking? How do you propose the energy of momentum be captured and returned to the AC compressor?

I have no idea what we're talking about. I get it for electric vehicles, but I can't imagine anything else...?

~YR

CF-Shane
08-30-2007, 02:56 PM
He wants to use an engine driven air compressor to stock pile energy captured through braking / general turning of the engine, to be released via reversing the compressor, in effect making it an air driven motor, upon acceleration.

My take on this is that most of the energy captured by this setup will be lost to heat, but that's just me.

nsmitchell
08-30-2007, 04:06 PM
I think Bail Out said something quite good. Use batteries instead of air pressure. Replace the compressor with a DC motor that charges a high voltage battery(s). On takeoff the process would reverse, the battery would power the motor to assist acceleration. I don't know how much torque a belt could assist the engine with though. Maybe a belt and pully with teeth or something. Food for thought anyway.

Yaris Revenge
08-30-2007, 04:11 PM
I think Bail Out said something quite good. Use batteries instead of air pressure. Replace the compressor with a DC motor that charges a high voltage battery(s). On takeoff the process would reverse, the battery would power the motor to assist acceleration. I don't know how much torque a belt could assist the engine with though. Maybe a belt and pully with teeth or something. Food for thought anyway.

Don't they already do that? They call it a Prius. :wink:

~YR

Thirty-Nine
08-30-2007, 04:19 PM
Don't they already do that? They call it a Prius. :wink:

~YR


x2:headbang: