Heat from auto rad and exhaust in to elctricity thru Stirling.

Moderator: stan.hornbaker

Forum rules
Be nice!
sqertsqert
Posts: 1
Joined: Tue Nov 19, 2002 1:57 pm
First Name: ROGER
Last Name: A

Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by sqertsqert »

IS ABOVE DOABLE IN VIABLE COMMERCIAL SENSE??
stan.hornbaker
Posts: 532
Joined: Thu Jun 20, 2002 6:01 pm
First Name: William S.
Last Name: Hornbaker

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by stan.hornbaker »

Simply put there is insufficient energy in the auto radiator and exhaust system and a large delta-T to operate a Stirling/generator to produce electricity economically.
ed___6110
Posts: 1
Joined: Sat Jul 10, 2004 5:14 am
First Name: Edward
Last Name: Sherlock

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by ed___6110 »

In view of the disgraceful ineffeciency of Internal Combustion
Engines surely there MUST be more than enough power wasted
through the radiator and exhaust pipe to not only run a normal
vehicle but in fact a vehicle approximately 50% larger than the
original.
Of course ICEs are only ineffecient at producing rotary force, as a
heat engine they are very efficient. This could mean a smaller
ICE to drive a big car thanks to Dr Stirling, what say you?
stan.hornbaker
Posts: 532
Joined: Thu Jun 20, 2002 6:01 pm
First Name: William S.
Last Name: Hornbaker

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by stan.hornbaker »

The Stirling engine concept is deceivingly simple. Almost anyone with some machining skills can build an engine that will run. Builing one that will run well is an entirely different matter. Ivo Kolin in his book, "Isothermal Stirling Cycle Engine," 1983 describes the design of a simple demonstration Stirling engine and the tweaking of that design to extract the last bit of performance over a period of some 12 years. Ivo states with regard to four isothermal cycles, Reitlinger, Carnot, Stirling, and Ericson "All isothermal cycles with regenerator are equivalent to the Carnot but only in the case where they are performed in its ideal shape. Here lies the main difficulty because the Stirling cycle is not easy to realise in practical engines.
There only a few Stirling engines currently in production for niche applications with comparatively expensive price tags.
It is unlikely that a Stirling engine will be forthcoming for any automotive application in the near term.
toocooltobe
Posts: 1
Joined: Mon Jul 26, 2004 5:02 am
First Name: Brian
Last Name: Werner

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by toocooltobe »

I don't know about using Stirling engines, but considering 2/3 the energy in gas turns to waste heat in the IC engine there is plenty of energy there to run the alternator, A/C compressor, pumps, etc.
I've had the same idea since I was I kid. If a Stirling isnt practical then a geared down steam turbine would be my next choice.
Of course I didn't have the money to develop the idea when I was 12. Now I'm 48 and I still don't!
bmccrary___2630
Posts: 1
Joined: Fri Dec 23, 2005 3:55 am
First Name: Bernard
Last Name: McCrary

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by bmccrary___2630 »

Hi Brian
Just read your response about the Stirling engine. I have had several ideas about running the engine myself. When I was a child we had a Servel refrigerator that cooled with gas. No electric. Also in Chicago there is a land fill that is not used any longer but there are small pipes coming out of it that burn off the gas. It has been burning for a number of years. Let me put the two things together. People that live in the country can have the small landfill to create the gas to run the Stirling engine. Doesn't take much. Also the freon gas (not from the land fill) could be used like the refrigerator to cool the Stirling engine. Can you visulize this concept? or am I smoking aspern.
rgmco
Posts: 11
Joined: Wed Mar 22, 2006 7:41 am
First Name: Dick
Last Name: Meloy

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by rgmco »

Automotive Stirling applications are non-starters for one important reason: engines are bought on a cost/kW basis, and no commercial Stirling will ever be cheaper than a gasoline engine on that basis. Further, to make a Stirling utilize waste heat from an exhaust efficiently, the engine must be too massive for a transportation application. ReGen Power Systems has designed 200kW and up Stirling engines to economically convert low temperature waste heat to power. Although our primary market is industrial waste heat, our engine could also utilize ICE exhaust heat from stationary power applications to produce additional power.
cighe
Posts: 1
Joined: Fri Jan 26, 2007 2:06 pm
First Name: MJ
Last Name: at-cighe

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by cighe »

Who cares about a transportation application? The concept
seems to be a way to use an old car as a household's
emergency generator with a micro-cogeneration/Stirling solution
for the waste heat instead of heating a swimming pool. The
swimming pool heating was supposed to be the match for a
small car. Something like the Fiat TOTEM matched to a Stirling
for another source of electric. To keep the emergency system
ready for service would involve running it periodically, shutting
down your grid connection and coasting. Now what say you...
binraking
Posts: 8
Joined: Mon Jun 18, 2007 10:31 am
First Name: David
Last Name: Ward

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by binraking »

Hello,

It would be necessary to crunch some numbers in order to give you even a WAG (wild ass guess) at to the efficiency of such a system, but here are some of the major factors that would have to be considered.

1. What would the surplus electricity be used for?

2. Is there a cheaper way to generate the electricity (other than using a Stirling engine to recover waste heat)?

3. How much surface area would be required (for reasonable temperature range) in order to generate enough evaporation?

4. Where would you put the tank of evaporant?

5. How would hauling the evaporant around affect fuel mileage? 6. What would be the initial and long term costs to the consumer?

7. What would be the benefit (bang for the buck)?

8. What do you do when it rains? Not much opportunity for evaporation when it rains, but one could catch the rain and use it to refill the evaporant tank.

I can already tell you there is a much more efficient way of handling vehicle exhaust heat. Eliminate it completely. In fact, eliminate all of the waste heat generated by the vehicles hydrocarbon fueled propulsion system by scrapping it in favor of one that generates a drop in temperature!

There are vehicles being used in France right now at this very moment that run on nothing more than compressed air. Thats right. You can breath their exhaust, and it is cool enough to be use as air conditioning! These vehicles emit nothing but AIR. Here are a couple of links to get you started, but try typing the words air car into Google and stand back!

http://www.theaircar.com/

http://www.gizmag.com/go/7000/

It looks like these cars are destined to be driven on every street ... Ah, I almost said in America, but right here at home is probably the last place you will see one. What I meant to say is that these air puffing little gems are destined to be driven everywhere but here. That is unless we get a grass roots movement started to convert/build our own on our own, since the American automotive manufacturers are way to busy wasting time developing hydrogen powered vehicles for which there is no infrastructure! Every service station in America already has an air compressor! Even your local Quickie Mart has a compressor to top up your tires with. Compressed air "fuel" technology would be very easy to merge with our exsisting infrastructure.

Where does a Stirling engine fit into this picture? Well, we need a power source to compress the air to put in our air powered car. We could mate a Stirling engine to the exhaust pipe of our local coal burning waste heat producing brute of a power station, and use that otherwise waste heat to compress air. And since air is pretty easy (and very non messy) to store. It would be easy to stockpile. And best of all if your air storage tank springs a leak nobody gets cancer!

We could pipe our "free" compressed air in the same way we pipe natural gas now. Imagine the growth potential for air-powered home appliances! A blow drier that actually runs on air! Oh My!

Seriously though, large scale stationary applications of Stirling engines are our best bet.

Think BIG! Someone once said that "If grasshoppers were as big as cows, we would all be eating grasshoppers".

V/R Dave

dplconsulting
Posts: 5
Joined: Wed Aug 01, 2007 10:37 pm
First Name: Dale
Last Name: Leier

Response to Heat from auto rad and exhaust in to elctricity thru Stirling.

Post by dplconsulting »

Apparently BMW thinks thars gold in that thar waste stream, as I understand they are working on a microsteam generator to produce electricity from a car's exhaust. And what would one do with all that electricity?

Well, there are these new cars out now called hybrids........?
Post Reply