alt.energy.renewable

"Punjab The Sailor Man" wrote in message
news:46f19935$0$28838$4c368faf@ ...
> We know the water in your engine is regulated to 180 degrees but could
> easily be regulated to 212 degrees especially if the water flowed
> through a jacket in the manifolds. Why not use the wasted heat energy
> for a steam motor to supplement the gasoline or diesel engine similar to
> the way electrics assist the gasoline engine. We know Stanley steamers
> were very efficient and powerful. Utilizing the heat waste from an ICE
> would increase the engine's efficiency greatly. Don't knock it unless
> you built a working model and it failed.

Actually, the thermostat in many modern car engines is set for between 220
and 250. The pressure and ethylene glycol keep it from boiling.

But steam at 212 degrees is only 0 psig. While there is some energy there,
the Carnot efficiency would only be (212-70)/(212+460) = 21%. Unless you
build a very complex 'steam engine' with regenerative reheat and multiple
stage feed-water heating, you probably won't get better than 10%. In order
to exhaust your steam engine to a 70 degree vacuum, you will need some
fairly bulky air-removal equipment since air-ejectors won't work at such low
pressure.

This would add between 500 and 1500 lbm of weight to the car. When
'cruising' down the highway at speed, the engine probably expends between 50
and 70 hp. Figure the radiator heat rejection is 1/3 of the total, so you
have a 'boiler' horsepower of about 20. With an overall efficiency of 10%,
your steam engine would add about 2 hp to the total. Awful lot of equipment
and weight for a gain of 2 hp.

I don't need to build it to know that its a bad idea.

daestrom