Solar Hot Air Engines

[Rich Carlstedt]

There is a current OT Posting on this forum that refers to Solar Electric to Hydrogen ( conversions) for green energy and I realized that not many are aware
that John Ericsson, famous as the Inventor of the Ironclad USS Monitor in the Civil War was also a Hot Air Engine inventor and developer among other things.
You may think that using solar energy is a recent creation, but it is not !
Over 150 years ago, Ericsson displayed his Solar Motor ....Mechanical energy obtained directly from the Sun !...at the Centennial Exposition in Philadelphia in 1876.
But during that period of the industrial revolution, Steam Power was King , and then shortly after that, Electricity became the Master.
Never the less, we should recognize this achievement made years before in utilizing Solar energy in all forms
My good friend Brent built a beautiful and accurate model of Ericsson's creation and you can see it on Youtube
I believe the original resides in a Philadelphia museum

https://www.youtube.com/watch?v=AP4XNkxjb2o

Ericsson also created a Steam Powered version with steam pressures of 35 PSI which you can read about here

http://hotairengines.org/solar-engine/ericsson-1868

We need someone here to build the engine so this post does not have to have a OT designation 😀

Rich

[Dan_the_Chemist]

We need someone here to build the engine so this post does not have to have a OT designation 😀

Maybe some clever Canadian ??? *hint hint*

[sid pileski]

Maybe some clever Canadian ??? *hint hint*

These engines require precision and close attention to tolerances to run.
They just don’t make enough power to overcome any binding or tight spots.

[BCRider]

That's pretty nice! I was going to type "that's very cool" but that would have been inaccurate....

At noon at the equator on the solstice apparently the sun produces 1120 watts/sq meter for a power rating of 1.12 Kw-Hrs per square meter.

This alters with latitude and time of day as the air between the collector and sun gets geometrically thicker. So let's say it's 600Watts/square meter at high noon with me being just above the 49'th parallel for giggles where I live. The collector he's using appears to be roughly 10" or 25cm in diameter based on the size of the fingers that sneak in and give the flywheel a nudge. The area of a 0.25m circle is 0.05 sq meters. So that would mean the engine shown in my backyard would be running with roughly 0.05 x 600Watts= 30 watts of potential input energy. So enough to do SOME work but I don't think I'd be using a solar motor to cut my lawn.... any time soon

Besides, last I read due to the relatively low temperature change as the air shuttles from cool to hot sides in a Stirling style engine the power we can get from them at the shaft is pretty limited due to the low degree of temperature change in the enclosed air. Something more would be needed to get more power at the shaft. Which I'm sure has been done. But with a good degree of extra complication I'm sure.

[Rich Carlstedt]

.................................................. ...............................
Besides, last I read due to the relatively low temperature change as the air shuttles from cool to hot sides in a Stirling style engine the power we can get from them at the shaft is pretty limited due to the low degree of temperature change in the enclosed air. Something more would be needed to get more power at the shaft. Which I'm sure has been done. But with a good degree of extra complication I'm sure.

Yes, they pressurize the chambers with inert gas like Helium and do it at 40 atmospheres pressure or more to get increased output ( HP )


Rich

[The Artful Bodger]

Besides, last I read due to the relatively low temperature change as the air shuttles from cool to hot sides in a Stirling style engine the power we can get from them at the shaft is pretty limited due to the low degree of temperature change in the enclosed air. Something more would be needed to get more power at the shaft. Which I'm sure has been done. But with a good degree of extra complication I'm sure.

These machines were moderately successful where they were used to pump cold water which of course provided the temperature differential.
https://www.rustyiron.com/Engines/ericssonhotairpu.html

[aostling]

'. . . My good friend Brent built a beautiful and accurate model of Ericsson's creation and you can see it on Youtube


https://www.youtube.com/watch?v=AP4XNkxjb2o

Nice engine. I wonder why he calls his Ericsson engine a "Stirling" engine -- they run on different cycles.

https://en.wikipedia.org/wiki/Ericsson_cycle

[RB211]

I couldn't watch the full video, why people must blast their taste of music in videos? I'd much rather listen to the actual motor run.

[BCRider]

The pressurized helium makes some sense. And using this or a true Stirling to pump cold water would be just about perfect.