Volkswagen Shows Thermoelectric Generator for Waste Heat Recovery
06 February 2009
Volkswagen showed a prototype vehicle fitted with a thermoelectric generator (TEG) for waste heat recovery at the “Thermoelektrik—Eine Chance Für Die Atomobillindustrie?” meeting held in Berlin, October 2008, according to a report on the International Thermoelectric Society website.
Volkswagen claims 600W output from the TEG under highway driving condition. The TEG-produced electricity reportedly meets around 30% of the car’s electrical requirements, resulting in a reduced mechanical load (alternator) and a reduction in fuel consumption of more than 5%.
Also on display was a system developed by BMW and DLR (German Aerospace) with a 200W maximum yield, and which has been used successfully for more than 12,000 km. Both BMW and GM are integrating TEGs with gasoline powertrains, with BMW planning to introduce TEGS in the 2010-2014 timeframe in the Series 5. (Earlier post.)
Does a Golf really use 2 kW electrical power just to maintain accessories while driving?
That's ridiculously inefficient, even including the water/steering pumps etc. Surely it would be cheaper and easier to simply replace the Victorian electrical system with something more efficient than to put in waste heat recovery (which I otherwise wholeheartedly welcome)?
Posted by: clett | 06 February 2009 at 03:26 AM
I suppose I have to wait for a cheap after market bolt-on.
Posted by: Peace Hugger | 06 February 2009 at 05:06 AM
I don't think electrical efficiency can be reduced much with the short runs of wire. Most of the load is right next to the alternator anyway.
Thats great if BMW can get the huge cost down by 2010. Maybe all that is needed is volume production to drive the cost down.
Posted by: GdB | 06 February 2009 at 09:22 AM
Yes modern automobiles are using nearly 2kW of power and the power budget is increasing with further electrification of systems on vehicles (further reason why a 42V system should have been implemented for vehicles already).
Fans (radiator & climate system), pumps (high pressure direct injection fueling, windshield washer, etc), "info-tainment", power windows, power locks, ignition systems, multiple processors, multiple sensors, electric power steering, power seats, heated seats, lighting, cruise control, the list goes on and on...
Posted by: Patrick | 06 February 2009 at 11:09 AM
I have a hard time believing that cars are drawing 2kw of electricity from the alternator all the time. That's 140 amps!
Isn't that the upper limit of what most alternators can produce? A quick search shows that you can get up to 200 amp alternators through the aftermarket - at 14.4 volts, that is nearly 3kw, so maybe there are some cars which normally pull over 1kw while cruising.
If that's the case, then yes, higher voltage electrical systems would reduce electrical losses by a large amount!
Would like to see some actual data if anyone has it...
Posted by: Dave R | 06 February 2009 at 12:16 PM
didn't bmw had a simliar waste heat recovery as well? they sure didn't gloat about its efficency boost, espically when one factors in R&D and the cost of manufacture.
Posted by: philmcneal | 06 February 2009 at 12:32 PM
No, it would not be 2kW constantly.
Analysis from september 2006:
Automotive Designline article
Posted by: Patrick | 06 February 2009 at 02:37 PM
That's amazing (and amusing) to see people like you failing to recognize what energy monster are our cars today, by today standard a car that have a engine less than 100HP is considered a golf cart, in the 70s people were happy with 50HP.
The same in your plate, there is about 10 calories of fossil fuel behind every calorie of food we swallow. Our civilization is extremely energy dependent and it will collapse if we don't find a way to curb that dependncy fast enough because it is clearly unsustainable
Posted by: Treehugger | 06 February 2009 at 06:30 PM
You guys have to learn how to read press releases. It doesn't say 600W is 30% of the load. The sentence with the 600W is separated from the sentence with the 30% by a period. Hence the claims are separate too. 600W is the probably the peak output (why else would you list it there). Then it implies that across all driving conditions (or a test-cycle that simulates typical driving conditions) it averages 30% of the electrical load.
Posted by: Floatplane | 06 February 2009 at 11:58 PM
Treehugger and Dave,
In Germany and Japan, many people are happy driving small cars with less than 100 HP.
Now there is a new 125cc motorcycle from the Indian manufacturer BAJAJ that can get 86km per litre of gasoline
i.e. 202 miles per US gallon.
The model of the bike is XCD 125.
Posted by: Jorge | 07 February 2009 at 08:44 AM
This type engineering may be why Volkswagon showed an overall sales increase last year. While other car makers tell tales of woe.
Posted by: Reel$$ | 07 February 2009 at 10:43 AM