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FormulaTwo
09-08-2006, 10:26 PM
Alright I have read about this. And i want to do it. Because i feel it can be done.

please remember
not an alternator
but a "wind generator"
useded to turn wind into electricity.

tried to change the post title****

I think a few of you have this confused.
In this case, the wind will be the EXHAUST flow.
On the models i have seen, they generate 8000watts, at 15mph of wind....

Now, im not sure how many RPMS it will be turning at 15mph, but it seems the turbo would spin a ton more. Which would most likely equal out to more power being generated.


A belt driven alternator in not efficient. This site has proven that.
For a performance car, a turbo is more efficient than a Supercharger, there is a big debate on this but regardless....

I want to make a way to charge my battery from my exhaust gas, instead of a belt, Removing all acc. belts from the engine.

A friend of mine has a t25 turbo from an eclipse sitting around..
I am thinking i can find a way to combine this with a wind generator


WIND GENERATOR like this....
http://www.survivalunlimited.com/windpower/windturbines/pma1.jpg

Somehow combining the rod from the wind generator to the center section of the turbo exhaust turbine.

According to this website, the generator it will produce 8000watts.
Now i know watts, amps and volts all work out together but i do not actually understand them or their formulas.

http://www.survivalunlimited.com/windpower/pmasc.htm

http://oldschool.supracentral.com/mods/turbo/te_new.jpg

Ideas......

- Use HF manifold (found on VX civics, HF crx's)
- Wind Generator (8000 watts)
- T25 turbo (Mitsubishi eclipse 95-99 models)
(break down turbo, Use "hot side")
- Make a new rod that will connect the hot side exhaust wheel to the wind generator)


Exhaust will flow down through manifold, into turbine housing. Spinning the wheel, which in turn will spin the Wind generator core.

I have everything i need to do it. I can weld etc....

My only problems are....

- A way to make a center section that will use bearings, INSTEAD of with an engine oil feed line.
- Finding a way to connect the generator shaft to the Turbo shaft and wheel.
- making it balanced.
- making it dependable
- finding a formula to figure out how many watts it will produce at certain engine rpms, and if it will be enough to charge the battery under normal highway driving etc...

If you guys can help me with this it would be appreciated.
Once again, I am not trying to TURBOcharge my car. Just replace the alternator with a new system.
I would draw up a picture but i do not have time right now. Maybe tomorrow
Help me out, we will make my car the guinea pig!:thumbup:

More pics,

http://www.turbosunleashed.com/shop/images/Turbine%20Wheel%20Clipping.jpg

omgwtfbyobbq
09-08-2006, 10:41 PM
I'm thinking you'll need an oiling system because the heat from the exhaust will probably cook any bearing/grease combination. There's also the matter of what the heat will do to the generator, etc...
If you're really dead set on doing this you might want to run the turbo normally, and instead of going through an IC to the intake, have it go through an impellor that's connected to an alt. But even then, it's way complicated and you'd probably be better off running an extra battery and charging it while at home.

Matt Timion
09-08-2006, 11:27 PM
I've been brainstorming this for a while now, but I don't have the knowhow. If you can get a working model, I am certain you can sell it to Honda enthusiasts.

FormulaTwo
09-08-2006, 11:31 PM
The only reason I do not want to run oil lines etc... is because, im worried that when i remove the compressor housing and make a way to connect the rod. That there will be an oil leak. Causing Oil to spray freely, or into the o2 housing .


An article on the generator idea.
http://www.greencarcongress.com/2005/09/tigers_exhaust_.html

Someone help me figure this out. I am determined to make this work!

JanGeo
09-09-2006, 02:32 AM
yup rpm will stop you dead before you go any further . . . turbo 60,000-150,000 rpm . . . alternator 15,000 rpm max . . . what makes you think you can get turbo power out of an engine at low power throttle use also.

onegammyleg
09-09-2006, 03:07 AM
Hi ALL

I rather like the redneck way instead :thumbup:

http://www.otherpower.com/images/bdwm5333.jpg

The funny thing about this picture , is that IT IS GENUINE :D

onegammyleg
09-09-2006, 03:20 AM
But seriously , the whole idea of running an ALT from exhaust gasses is not a very good one.
As pointed out in other posts , exhaust gas flow would be too little to turn it at idle or light throttle and it is likely that you rwould need a gear box to reduce the rpm to the ALT.
But that would again make for low output at any normal driving speed at lite throttle.

Even IF it did mechanicaly work, th epower needed to turn the ALT is not free.
The 1 or 2 HP (?) needed to turn it (at full output) would be shown as a restriction on the exahaust.
I would guess that the motor would run worse with that setup than just running a conventional belt drive.

What you need is to get FREE power !!! (or almost free is good too)

How about , running an electric clutch on the ALT pully.
So that it only locks up and starts charging at idle or deceleration.
The clutch can be switched in or out with a simple vac pressure sensor., and the parts to do the clutch can be salvaged off a air con compressor.
CHEAP MOD

KaChing , almost free power :D

DaX
09-09-2006, 07:04 AM
First problem - RPM's...as discussed above, but this can be overcome with gearing.

Second problem - Heat...I used to run a turbocharged Civic...the turbine housing temperatures were insane...preventing this heat from transferring into the generator is going to be very difficult.

Third problem - Torque...you'll need to determine the torque required to turn the alternator at full load through a range of RPM's (essentially dyno testing the alternator at full load). Then you'll need to see if the turbine can provide such torque at each RPM (whether you use gearing or not).

Not trying to slam the idea, just proposing some issues I see right off the bat.

MetroMPG
09-09-2006, 07:37 AM
but then I thought, all that fooling around and expense to potentially save what?
On a 3-cyl Metro? About 10% FE increase @ 70 km/h (running off the battery):

Alternator v. no alternator (http://www.gassavers.org/showthread.php?t=1074)

Matt Timion
09-09-2006, 09:36 AM
But seriously , the whole idea of running an ALT from exhaust gasses is not a very good one.

I actually think it's a brilliant idea.

http://www.greencarcongress.com/2005/09/tigers_exhaust_.html

http://66.102.7.104/search?q=cache:EJUiTJBwAe8J:www.gzvb.de/fileadmin/user_upload/abstract_hybrid2006_visteon_quinn.pdf+%22tigers+ex haust%22&hl=en&gl=us&ct=clnk&cd=8&client=firefox-a

FormulaTwo
09-09-2006, 09:55 AM
please remember
not an alternator
but a "wind generator"
useded to turn wind into electricity.

I think a few of you have this confused.
In this case, the wind will be the EXHAUST flow.
On the models i have seen, they generate 8000watts, at 15mph of wind....

Now, im not sure how many RPMS it will be turning at 15mph, but it seems the turbo would spin a ton more. Which would most likely equal out to more power being generated.

FormulaTwo
09-09-2006, 10:00 AM
Link to wind generator.

http://www.nrel.gov/wind/animation.html

Im wondering how many rpm, the exhaust turbine would flow at IDLE, and under 2500rpm....
This would be my operating range of engine RPM.
also,

the rpm issue could be fixed with the exhaust wheel. TO turn less rpm.

omgwtfbyobbq
09-09-2006, 10:13 AM
As a concept I think it will definitely have it's day. Especially when paired with a low disp, twincharged gasoline engine that drives like a diesel since a turbo doesn't use all the energy from the exhaust all the time, and a supercharger is needed for more air/power at low rpm. But... It just seems like something that's not practically doable for the DIY'er. I think getting a few deep-cycle batteries and a solar charger is the ticket to the same savings in mpg w/o all the hassle.

Kraig
09-09-2006, 11:26 AM
I think you also need to consider the rotating mass of the alternator versus the mass of the compressor side turbine of a turbocharger. I've rebuilt my turbo before and the impellers are relatively light. Not sure if the alternator would spool up worth a darn and would actually pose as an exhaust restriction (trying to accelerate the large mass of the armature) giving poor performance and efficiency. I would imagine you would build up alot of pressure in the exhaust manifold (a bad thing) causing the exhaust to actually back flow into the combustion chamber diluting the incoming air/fuel charge with less than desirable results. I think you would actually get worse FE. On a regular turbo setup it requires some power to actually run the turbo (nothing is free) but the performance gains significantly offset the slight loss. On your proposed setup you would just see the loss with no performance gain (perhaps a small efficiency gain). I doubt this small gain would overcome the effort required to get a heavy armature to spool up.

Just my 2 cents worth. I've driving turbo 4 cylinders since 1985 ....

Kraig
09-09-2006, 12:25 PM
Another 2 cents worth. A turbo doesn't make boost unless there is a load on the engine (acceleration), when you're cruising along the impellers are just spinning and not creating boost. The only way you'd create enough exhaust energy to run an alternator would be under acceleration. You'd probably have to do alot of acceleration to keep your battery charged. Heck at cruising speeds you might not even have enough exhaust energy to spin the armature and all you'll have is a highly restrictive exhaust most of the time (an impeller spinning slower than the speed of the exhaust gases would be a restriction). I'm not trying to discourage some from trying this, but I don't the effort would be worth it personally.

FormulaTwo
09-09-2006, 02:34 PM
Some people say it would spin too fast.
Some of you say it wouldnt spin enough to generate anything because of the friction.

I do not personally feel that restriction would cause exhaust to back up. Keep in mind these things are easily turned at 10mph. Ofcourse thats with a big enough fan blade to turn it.

But i think that with the right exhaust wheel, you could get the shaft to generate enough electricity at idle.

Here is a chart for wind generators and what they produce at each MPH.

http://www.greeleynet.com/~cmorrison/windcalc.html