New hair brained idea...

[TheTopher]

So a couple weeks ago I found a thread on here that was talking about an alternator that was powered by exhaust gasses, very similar to how a turbocharger is powered by them. It's essentially free electricity. I had a little hard time finding the thread for a link, but when I have some more time I'm going to go back and look for it. Anyway I also found a thread about using the car's electricity to create hydrogen from water to help boost the engine, and the general consensus was that since it's putting added strain on the engine to create the boost the net gain is nothing. This page However, what if this hydrogen system was powered by one of the new "turbine alternators" (I don't remember the actual name for it) Since it doesn't take any added stress on the engine to power this type of alternator, would this make the hydrogen boost idea feasible?

Just a side note. I don't have the resources to actually try this, I just thought it was an interesting idea and wanted to hear other's thoughts on it.

[SVOboy]

I wouldn't go out chasing hydrogen generator dreams...it would make much more sense to work on replacing the alternator with a generator running off exhaust gases.

[KJSatz]

I agree.

[Johnny Mullet]

I thought that way back in the 50's and 60's they made a Starter/Alternator combo unit that reduced weight by incorporating into one unit. I wonder why this never caught on?

[metroschultz]

Ooh, Ooh, I know this one,
Mr Mullet,
!Pick me!, !Pick me!

O.K. Schultz,

Ooh, they couldn't get the driving public to wrap their arms around it cause it was so noisy.
The starter/generator was a concept for lighter weight and less mechanical problems, but it started the engine, and was driven off the ring gear on the flywheel.
It was VERY NOISY
Then in the late 50's alternators came into the field and generators went away completely.
The starter and alternator in a car of today weigh less added together than one of the starter/generators from the 50's

However, up into the 80's you could find some motorcycles that used a starter/generator (and there may still be some today, but I haven't seen one in a while)

ooh ooh that's it, isn't it Mr Mullet?

Yes, I see you did your homework last night,
what about the rest of you slackers?

Hmmmmmm?

[Johnny Mullet]

You crack me up

[Formula413]

But what about the fact that the exhaust gas has to be pushed through the exhaust system (and in this scenario through the alternator turbine) by the exhaust stroke of a piston, which is in turn being powered by the firing stroke of another piston? Is this really any different than the idea of having a wind driven alternator? The power ultimately always has to come from burned fuel. The only sound idea I have ever heard for capturing wasted energy from the exhaust was the idea of a gas/steam hybrid, where the hot exhaust gasses heat water to power a small steam engine to supplement the ICE.

[dentprone]

mmmmmm......gear noise

[jamesqf]

Originally Posted by Formula413

But what about the fact that the exhaust gas has to be pushed through the exhaust system (and in this scenario through the alternator turbine) by the exhaust stroke of a piston, which is in turn being powered by the firing stroke of another piston? Is this really any different than the idea of having a wind driven alternator? The power ultimately always has to come from burned fuel.

No, because the exhaust gas isn't really (or mostly) pushed by the piston, but by the power of its own expansion. (Think for instance of the difference in the noise level of an unmuffled exhaust and an air compressor.) The power captured by the turbine comes from the waste heat in the exhaust gas stream. It will be hotter upstream, cooler (and thus lower pressure) downstream.

[SuperTrooper]

GM hybrids use a belt driven alternator/starter, operating at 36 volts.