Math Question

[John Napoli]

Unless some real efficient heat/electric device was available, and used to
drive the car, not much of a gain will be seen.  Heck, if such an
efficient direct heat/electric capability existed, we could replace our
engines with oil burners (like the one o\in your basement)!

Power plants have 2 advantages.  THey don't move.  So weight of the extra
equipment isn't a problem.  And they are amortized over something like
thirty-five years.  Helps with the costs.  Now while some of us might have
overweight project cars that never move and just eat dollars, that is not
the point!  :)

So I expect that this issue will remain pretty much a sore point unless
somehow we figure out how to use the waste heat to perform mechanical
work.  Your car just does not use enough electrical power to gain much by
eliminating the alternator, although of course it is a step in the right
direction.

John


On Mon, 16 Sep 1996, hoss karoly wrote:

> John Napoli wrote:
> > 
> > This issue of thermodynamic efficiency is one of my hot points (ouch).
> > 
> > Fossil fuel plants use every trick in the book to recapture all the
> > 'waste' BTUs that they can.  If you neglect the power used to run their
> > pollution devices (a parasitic loss), their overall efficiency is pretty
> > good - I recall numbers in the mid-40s.
> > 
> > Our gasoline engines in our cars do nothing to utilize the energy in the
> > waste heat.  Arre they 10%? 20% efficient overall?  I doubt 20% but lets
> > go with that number.
> I had the same feeeling before .
> in fact I plan to build some peltier-cells on my engine
> to charge my battery 
> who knows ? maybe I can eliminate the generator and save power
> 
> BTW does anybody knows how the H-O cells work ? is it possible to build
> one
> wich work with gasoline and air to produce electricity ?
> the heat-cells work at a 70-80% eff. range
> 
> bye
> charley
> 
> 
>