Turbo-powered alternator

[serialk11r]

That's great, only problem is a non-hybrid vehicle has no way of using 6kW!
I want to try taking a rather large turbine and gearing it straight to the crankshaft via pulley, it would do best at high rpms where typical cam phasing systems have the exhaust opening earliest.

For just generating enough electricity, getting 300W from heat alone isn't horribly difficult I think. Aluminum heat exchanger, 2kg worth of thermoelectric generators, and aluminum waterblock will go a long way. This would cost several thousand dollars, but this turbine generator would too.

[Tesla]

Originally Posted by Air-Hybrid

"TIGERS (Turbogenerator Integrated Gas Energy Recovery System) is a water cooled switched reluctance generator coupled to an exhaust driven turbine. It is capable of operating in exhaust temperatures > 900ºC, at speeds up to 80,000rpm, delivering a shaft power of 6kW"

Controlled Power Technologies... TIGERS

Good find,
I would like to see a side by side study done on two identical vehicles, one std the other with the Turbo generator for say 5,000km, then swap the turbo unit over to other vehicle. Use the same driver for bothe vehicles, but driver is not aware whether the vehicle is std or with Turbo Gen.
Everything else in the vehicles must be identical and just using an appropriate section (same length as turbo) in the exhaust on the non turbo vehicle, so flow charachteristics are not modified in any way.
Fuel economy could be compared effectively then.
That type of evaluation would then prove conclusively if it was a viable concept.

[mans]

Originally Posted by serialk11r

That's great, only problem is a non-hybrid vehicle has no way of using 6kW!
I want to try taking a rather large turbine and gearing it straight to the crankshaft via pulley, it would do best at high rpms where typical cam phasing systems have the exhaust opening earliest.

For just generating enough electricity, getting 300W from heat alone isn't horribly difficult I think. Aluminum heat exchanger, 2kg worth of thermoelectric generators, and aluminum waterblock will go a long way. This would cost several thousand dollars, but this turbine generator would too.

are u sure the thermoelectric generator is so expensive? have a look:

starting at like $5 POWER GENERATION TEG - HIGH TEMP THERMOELECTRIC PELTIER | eBay


and going up to $38
http://www.ebay.com/itm/THERMOELECTR...item27c36f54e4

it just depends on the item's size and power.
I'd imagine a bunch of these attached in the appropriate manner to the exhaust manifold (or farther down the pipe if it's too hot over there) should bring about enough power to run our ignition coil, headlights and fuel pump as necessary

the question is how do you hook them up properly...
I welcome all feedback

[serialk11r]

A Tmax of 180C is pretty useless for power generation. Sure you could use like 50-100 of them on your exhaust, but weight and cooling become a problem.

Commercially available ~300C peltiers that size are 100 dollars for about 15-20W capacity running at max delta T. If you're using the car's existing coolant loop at 90C even with an "intercooler", you'd be lucky to get more than 10W from each one.

In addition if you're running them at max temp, the ones I've seen put out 15V or so which is too high. If you wire that straight to the battery you'll end up bleeding off a few percent of the precious power through internal resistance.

Ideally we have the turbine for pressure recovery, and then the TEGs for heat recovery working together. On a hybrid car of course.

[mans]

Originally Posted by serialk11r

In addition if you're running them at max temp, the ones I've seen put out 15V or so which is too high. If you wire that straight to the battery you'll end up bleeding off a few percent of the precious power through internal resistance.
.

u sure? dont alternators charge at 14+ volts anyway and lose a drop as a result?

so 15v shouldn't be too terrible

[serialk11r]

14V is the limit for charging a battery, over that you damage it (I think). To safely provide thermoelectric power to the system it has to be at less than 15V, and you can do this by either converting it or intentionally reducing the capacity so that it bleeds off the voltage via internal resistance.

[Air-Hybrid]

Originally Posted by serialk11r

That's great, only problem is a non-hybrid vehicle has no way of using 6kW!

True, but note that 6kW is the max. shaft power - ie. the 2-litre ICE shown has to be going some to push the exhaust stream hard enough for 6kW, plus the best electrical efficiency is 90% and only for high voltage.
I still reckon $/kW a turbo-machine like this would be better value than the TEG option, at least until the technology matures. And providing, as you say, you can apply 6kW to something ... BAS (belt alternator starter) type hybrids aren't beyond the backyard tinkerer.
The costliest part for one off build of something like the TIGERS design would be the high-speed generator, but the turbo could be 2nd hand and relatively cheap.

Originally Posted by serialk11r

I want to try taking a rather large turbine and gearing it straight to the crankshaft via pulley, it would do best at high rpms where typical cam phasing systems have the exhaust opening earliest.

I'd still go via the electrical route due to the differential in revs the turbo wants to run at against those of the engine, ie. at mid-revs say 2500 on 3/4 load the turbine will still be most efficient spinning near to it's maximum of 80k. Also there is no need to plumb in additional bypass on the exhaust.
With the power routed -> Turbo-Generator-PowerController-Motor a cut-out is easy, with no concerns about choking the gas-flow. Hey, throw in an ultracapacitor bank as well for that extra kick!

[mans]

Originally Posted by mans

are u sure the thermoelectric generator is so expensive? have a look:

starting at like $5 POWER GENERATION TEG - HIGH TEMP THERMOELECTRIC PELTIER | eBay


and going up to $38
THERMOELECTRIC POWER GENERATION TEG MODULE - 62mm x 62mm - **QUALITY USA MADE** | eBay

it just depends on the item's size and power.
I'd imagine a bunch of these attached in the appropriate manner to the exhaust manifold (or farther down the pipe if it's too hot over there) should bring about enough power to run our ignition coil, headlights and fuel pump as necessary

the question is how do you hook them up properly...
I welcome all feedback

these dude's that I've ordered came in the mail the other day.
I tried them out by putting an inverted tin pan on the stovetop with a very small fire on. the inverted pan got quite hot and I tried the cells out on top of it.

they are useless. I had trouble getting the voltmeter to read .4v

when operating well they read like .32-.35v

total garbage.
if you put in 12v they get frightfully hot in 5 seconds but if you heat the unit you do not generate frightful electricity

all right, next idea please

[silverinsight2]

Originally Posted by mans

when operating well they read like .32-.35v

total garbage.
if you put in 12v they get frightfully hot in 5 seconds but if you heat the unit you do not generate frightful electricity

you need ~ 46 of them in series to get ~14vdc (14v/.3v=46 units)

[kingsway]

You also need to cool one side as you heat the other, if I'm not mistaken. It's the difference in temp between each side that does the work.

Maybe you can mount them on an old cool-box and use them to cool your beer! (or heat it if you get the polarity wrong)