Stirlingengineforum.com

Hello everyone,

This is my first post and I'm a total noob so please bear with me.

For a while I've been fantasizing about powering an engine via Fresnel lens which is then connected to a generator which then is connected to my house. I live in Chicago and the sun beat down pretty hard this past summer so I was hoping that it would be possible to really generate some free electricity. I found a Fresnel lens manufacturer in China that says that claims that on a good day their lens can heat a point up to 800 deg C.

I see that people have tried some of this before and I was wondering what kind of Wattage people have managed to create? I purchased a book that described the creation of a 5 horsepower, rice-husk fed Stirling engine and thought something like that would be awesome as a component of a system like this.

Thanks,

mj

jaskiewiczm, hi, I'v got a 22" x 18" fresnel lens (it was made to fit in front of a TV screen). Where I am is just north of lat 43deg sth, and in mid summer I'v managed just a bit over 5 watts from a motor that produces a similar power with LPG. See my gallery, and my motor labled My second engine.
I'm sure the focal point is a bit more than 800deg with full sun, nearer to 2000deg, but it depends on atmospheric polution, and we are fairly free of that here.
To operate a power system like this requires a method of tracking the sun, to keep the lens focused on the hot spot on the motor. If you use lenses similar, or larger than mine, there could be up to six or so to each motor, a four ft sq lens might have a focal point about one inch dia. Ian S C

Hi Ian,

Thanks for the reply. I know about the sun tracking. I have an the .NET version of the Arduino (the NETduino) that I was hoping to purpose for precisely such a task. I found a 1 meter diameter lens with a circular pattern.

What does LCP mean? I've seen that acronym a bit here in the forum but am unfamiliar with it.

jaskiewiczm, I don't know about LCP, but if its LPG that I used, that means "liquid petrolium gas", I think its known as that in other countries.
Could be worth getting a few of those lenses, if you can mount them on a frame so that the focal points are next to each other rather than on top of each other, you will heat a good area. Watch it, this is dangerious, the one I used focused down to about one mm spot, and etched a line across the stainless steel hot end, and it is quite capable of burning a hole in stainless. Ian S C

Lens it is - here is where I go and this guy knows Stirlings as well!!! EDIT - I would look at the one that is not SPOT but rather the one with a enlongated focal point and place multiple hot cylinders in a row!!!

http://www.greenpowerscience.com/


Cheers!
Coog