Exhaust driven generator (Theory , not real device)

[RBphoto]

Mods, please note, this is a theorethical post, but quite technical.

Since we have been talking about electric superchargers, would one not consider an alternator driven by the exhaust? I give the following reasons for this:

1) free energy from exhaust (provided the turbine gives little restriction to flow , maby as much as stock when idling)
2) Variable backpressure can be achieved (such as that on the higher end GDI cars with varable area exhaust's) by changing electrical load on the alternator
3) For cars with a massive amount of ICE, could help save the alternator/ battery
4) Faster charging of batteries for electric supercharger.

Anybody know what the actual power output of a turbo exhaust shaft is?

[Rory Phoulorie]

bhagan, get the mods to change your 2NR name to Red Green. You could explain it with reference to a traffic light since this is an automotive based website, but you kind of have the logic of the real Red Green.

<embed src="http://www.youtube.com/v/yJJrjDI5xSQ&rel=1" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed>

[VexXx Dogg]

the velocity of the air being moved might not be enough to drive a conventional alternator.

this will create backpressure that will blow your motor like a venezuelan wh0re.

[bushwakka]

yes...the alternator will have to be one built for the purpose, but why would you want to do this cuz u'll only get good power output after the turbine spool up......the 'supercharger' design of alternators is far better........no energy is 'free' my friend.....it comes with inconvenience and cost.....in this case the backpressure WILL cause a drop in efficiency, and i daresay more than that of conventional alternators

[katastrophic]

Rory Phoulorie,

[xxSTAY TUNEDxx]

nice idea but i dont think it's worth it.

[RBphoto]

nice idea but i dont think it's worth it.

I was waiting for this reply ^^^^^ We all have ideas and might think of something out of the ordinary, or see something on an onbscure web page that claims that it is the schizzit, and just ask a question if it has been done before, anybody know about this technology, where I could buy it just to see it it works, if it inexpensive enough.

Even if you explain it is a theorethical device and you want to just discuss the principle of operation, some not so bright ppl, who can't think past if it not avalible in the bamboo, it cyah work will post up crap like rory. I kinda dissapointed in rory because I actually respect his oppinions on many issues and I have learnt a lot from him on this very forum.

bushwakka, my thoughts exactly, but people do many strange things with cars for specific purppouses. I even heard of ppl wanting to put concrete in their body panels for SQ competitions. Practical for an every day driver...of course not. What if some soundoff man want some extra juice for his ride for a few hours and he hook this up to his car, raise the idle a little and presto. PPL do all kinda stuff to make the best, loudest low frequency hum in the world, even outfitting a armoured car for rigidity. Useful to everyday driving? no, but they need juice for that. If they could eliminate a battery or two, maby they could have room for extra speakers?

VexXx Dogg, not talking about a conventional one, a purpouse built one that will regulate its output to keep backpressure minimal, only for scavenging, still using the belt driven factory alternator, not a replacement.

Does anyone know that the Prius has no brakes? It scavenges the energy in braking by turning the braking energy into electrical energy. What if my theorethical device was hooked up to the engine on that car, a lil 1.3, and some of the exhaust energy was scavenged to charge the batterry, and they got some 5mpg more?

Is it worth it? The price of gas in the europe in some places is about 10U.S. per liter. Would it be worth it then to us? That is more than ten times your gas bill in sweet trini, xxSTAY TUNEDxx. This device might only have value on a hibrid though.

Everyone is looking to scavenge energy (as in the prius), and some modifiers are even using solar panels on stock cars to help their alternator drive their rediculous amounts of ICE.

I think Red Green has more imagination than some tuners.

[boom]

PPL do all kinda stuff to make the best, loudest low frequency hum in the world, even outfitting a armoured car for rigidity. Useful to everyday driving? no, but they need juice for that. If they could eliminate a battery or two, maby they could have room for extra speakers?

Huh? What does the rigidity of a the car has to do with the juice? I know the stiffening of cars in spl compitions is to decrease the amt of energy (air moved) being lost due to flex and focas on hitting the pressure sensor..More speakers arent nessesarily a good thing cancellation, added costs in amps/build..

Everyone is looking to scavenge energy (as in the prius), and some modifiers are even using solar panels on stock cars to help their alternator drive their rediculous amounts of ICE.

Link to this source of info, thats something I would really wanna follow up on.. I ent say the idea is a bad one eh but I just dont see the whole idea comiing together soon cause if we trying to DECRESE fuel emmissions then what we gonna use to drive the alternaters? Maybe in a commertial application this could work like on a oil rig or something...

[RBphoto]

PPL do all kinda stuff to make the best, loudest low frequency hum in the world, even outfitting a armoured car for rigidity. Useful to everyday driving? no, but they need juice for that. If they could eliminate a battery or two, maby they could have room for extra speakers?

Huh? What does the rigidity of a the car has to do with the juice Two separate issues, the impractical for everyday mods: stiffening, Extra juice from the scavenging alternator to make some room. That was an analogy, so doh study it too much, open your one ched on that.? I know the stiffening of cars in spl compitions is to decrease the amt of energy (air moved) being lost due to flex and focas on hitting the pressure sensor..More speakers arent nessesarily a good thing cancellation, added costs in amps/build..

Everyone is looking to scavenge energy (as in the prius), and some modifiers are even using solar panels on stock cars to help their alternator drive their rediculous amounts of ICE.

Link to this source of info, thats something I would really wanna follow up on..

http://www.greencarcongress.com/2005/12 ... oofto.html

Can't find the one I saw with modifiers putting a solar panel to help on a pimped out scion. They did this to another car on pimp my ride though.

I ent say the idea is a bad one eh but I just dont see the whole idea comiing together soon cause if we trying to DECRESE fuel emmissions then what we gonna use to drive the alternaters? Maybe in a commertial application this could work like on a oil rig or something...

Like I said in the title bredz, is just theorethical, we don't need to worry about how this bolting up on our cars in the near future

[/b]

[Rudman]

O.K. Bhagan.....I see your point. Scavenging energy from the waste gases of a combustion engine.

But since we are on the topic of scavenging wasted energy, think about it. The combustion process in a car is only 25-30% efficient in producing useful work. That means of the 100% potential energy contained in fuel, only 25-30% is converted to useful energy to move the car. The vast majority of the fuel's energy is expelled as heat!

It would seem to me that if, somehow, you could scavenging even half of the heat energy expelled, then you would really be on to something! That would really be an invention worth looking into!

Don't reinvent the turbo to drive an alternator, find a heat driven alternator!....

Just my thoughts.

[5fwd]

delete

[Hook]

O.K. Bhagan.....I see your point. Scavenging energy from the waste gases of a combustion engine.

But since we are on the topic of scavenging wasted energy, think about it. The combustion process in a car is only 25-30% efficient in producing useful work. That means of the 100% potential energy contained in fuel, only 25-30% is converted to useful energy to move the car. The vast majority of the fuel's energy is expelled as heat!

It would seem to me that if, somehow, you could scavenging even half of the heat energy expelled, then you would really be on to something! That would really be an invention worth looking into!

Don't reinvent the turbo to drive an alternator, find a heat driven alternator!....

Just my thoughts.

as he mention the turbo-styled alternator idea, I was thinking something along the lines of a steam-driven or similar turbine-driven charging device incorporated into the vehicle's cooling system...haven't given it much thought past that, but one of you brainiacs should be able to come up with something

[Rudman]

Yea, I was thinking along the same lines too........a heat exchange device that serves as the engine's radiator, but recovers the heat to generate steam to drive something...or whatever....

[RBphoto]

Actually Hook,
Just the temperature differential itself could get you juiced up.

http://freeenergynews.com/Directory/ThermoElectric/

There is the sterling engine, and the thermoelectric effect which can be used to cool the engine and provide electricity.

Thermodynamics is not my forte, but I guess if you inject water at the right point in the turbine, you might get some gains in from the water boiling and expanding quickly, and helping to drive the turbine and produce more electricity. The disadvantage will be even greater back pressure on the engine.

[boom]

bhagan, I was just asking bout my misunderstandings, Like I said Im not against it, Im looking forward to it in our heavy equitment...

[Rory Phoulorie]

Even if you explain it is a theorethical device and you want to just discuss the principle of operation, some not so bright ppl, who can't think past if it not avalible in the bamboo, it cyah work will post up crap like rory. I kinda dissapointed in rory because I actually respect his oppinions on many issues and I have learnt a lot from him on this very forum.

I think Red Green has more imagination than some tuners.

You know you have contradicted yourself here. If you actually took the time to watch the Red Green show, you would realise that, as stupid and funny as he makes these things seem, it actually requires alot of engineering ingenuity, as well as common sense, to come up with the ideas.

So where you get this idea saying that I posted up crap, I really would like to know. It is obvious that you haven't recognised that I was acknowledging your original (I hope) idea through my sense of (dry) humour. For this I apologise.

Oh and by the way bhagan/Red Green, the Prius does have brakes. But, it uses regenerative braking to recover some of the energy that would be lost during the braking procedure (since there is forward motion without any applied thrust during braking) and convert it into electrical energy to improve the efficiency of its hybrid system.

With respect to solar panels on cars, this has been done already. The JDM Mazda 929 from the early 1990s used solar panels to power an extractor fan to keep the interior of the car cool during hot weather conditions.

[bushwakka]

the best way i can think of to better harness the heat produced by heat engines is the principle of that of the thermocouple.....remember this from physics guys? A temperature difference on conductors causes a potential difference and hence causes an electric current to flow

so if you could somehow link a colder source to the heat engine, then u can get a current flowing in the conductor linking them, and thus producing energy

thus direct Heat--->Electrical energy conversion vs.
Heat---->Mechanical Energy----->Electrical energy

[Dave-ve]

if you want to recover wasted heat energy you can use a Stirling engine to drive a generator. the only problem is that these engines are expensive to build.

check it out. http://en.wikipedia.org/wiki/Stirling_engine
there is a demo model that can run off the heat from a coffee mug.

http://www.metacafe.com/watch/475665/stirling_engine/

[buzz]

/\/\ some real interesting stuff there man

[X2]

With respect to solar panels on cars, this has been done already. The JDM Mazda 929 from the early 1990s used solar panels to power an extractor fan to keep the interior of the car cool during hot weather conditions.

Many luxury cars still use this... Mercedes and BmW have it as an option on certain models... it also operates periodically when the car is parked to keep air flow up so the car isn't too stuffy when you get in.


Honestly, it's less of a matter of an available source of energy (exhaust) than thinking outside the box.... alternators are heavy... at least one that can produce useable power (coil windings aren't light) and a turbo is much easier to turn than an alternator.... whilst a turbo may only consume about 5-6 hp on an engine due to blocking exhaust flow, something as heavy as an alternator would consume much more... I would hazard a guess of over 10hp in restrictions.... whereas a standard crank driven alternator probably only uses about the same.

Superior power scavenging effects might be seen by rather running a turbo on a smaller engine, hence making more power from less displacement, less fuel, by having a more efficient engine.... rather than trying to scour energy in a less efficient manner.

[xxSTAY TUNEDxx]

O.K. Bhagan.....I see your point. Scavenging energy from the waste gases of a combustion engine.

But since we are on the topic of scavenging wasted energy, think about it. The combustion process in a car is only 25-30% efficient in producing useful work. That means of the 100% potential energy contained in fuel, only 25-30% is converted to useful energy to move the car. The vast majority of the fuel's energy is expelled as heat!

It would seem to me that if, somehow, you could scavenging even half of the heat energy expelled, then you would really be on to something! That would really be an invention worth looking into!

Don't reinvent the turbo to drive an alternator, find a heat driven alternator!....

Just my thoughts.

now that's an good idea.