Fresnal Solar Stirling Engine

Discussion in 'Energy & Electricity' started by cannon, Oct 8, 2008.

  1. cannon

    cannon Member

    Has anyone ever heard of a stirling engine? I think it is possible to convert a gas one into a stirling engine if you get a 5 horse power one then you can read this wikipedia page to get an idea of how to make enough energy to power the thing during the day

    Scroll down to "Dish Designs" and read
    "A parabolic solar dish concentrating the sun's rays on the heating element of a Stirling engine. The entire unit acts as a solar tracker."

    There are videos on youtube of a stirling engine being powered by a solid steel heating element tube and a fresnal lense, now extend the heating tube a great length, make it completely solid so it holds more heat, and you have alot of energy to work with for powering your house provided you follow the trough formation as the article describes and have enough fresnal lenses

    Heat storage can also be increased various ways if you research it to get energy at night
  2. carnut1100

    carnut1100 Well-Known Member

    Should work.
    There is a town in the Australiwn Outback that uses parabolic dishes to boil water to steam and drive a steam engine generator.
    You need good sunlight for that though.
    Stirling engines are cool. I have seen a home made one running off LPG that is on an outboard boat motor and drives a 10 foot dinghy at 3 knots.

  3. Jack

    Jack ExCommunicated

    G'day folks

    i have built a few stirling and built a solar powered one

    Parabolic dish heats a seal glass chamber drives the engine and drive the generator, not great output and a cloud will put out the lights but if one was scaked up it should work

    but lamina flow engines have a greater torque output for the same input of energy

    A Simple Lamina Flow Engine

    these are models but there is a bloke here building one with a 4000 CC piston and then he plans to make a 4 cylinder version that he hopes will have the same output as a small ( 10 KvA) genset..

    Los alamos national labs (LANL) has a great lab working on lamina flow engines

    i built a cone drive solar engine in South Australia some years ago
    it was a hybrid design that also heated water during the day which was stored in the cone shaped tank inside the cone plexiglass surround.

    worked well..

    it was 22 ' tall and 18 wide at the base

    View attachment 1

    View attachment 2
    Last edited: Oct 10, 2008
  4. dragonfly

    dragonfly Member

    Anyone who has built one, did you use some instructions off of the internet? I am looking to build a small scale stirling engine that runs off of a candle or whatever heat source. The plans I found had the usage of JB Weld which I find melts rather easily when put to heat so therefore will not work to hold my engine together.
  5. darkling

    darkling Member

    I looked at that picture and if only one of those things is more powerful than an equally sized solar panel... then maybe it is a more powerful way to harness energy.
  6. carnut1100

    carnut1100 Well-Known Member

    If you want to build a small one just for fun, go to and obtain one of their free samples of a precision dashpot.
    This is a small precision glass cylinder with a graphite piston.
    You remove the adjusting screw from the top and you now have an inlet port for the hot air.

    The picture is of one I took a photograph of last year at a show. The displacer piston is a piece of styrofoam, the cylinder and piston are an airpot dashpot, and the flywheel is a biscuit tin lid.
    It runs on a cup of hot water.
    Quite simple to build.
    I haven't done one yet, just nevef seem to have time to do it, but I have the dash pot.
  7. carnut1100

    carnut1100 Well-Known Member

    Here are a few pics I got of Stirling engines at a show the other day.

    Here is a small model built with an Airpot dashpot as a piston

    Here is a little one of an unusual design, it fits on your hand and stis there running along at 4000 rpm

    And here is an outboard boat motor that pushes a 10 foot dinghy at 3-4 knots

    I have videos of them running but not sure how to get them on here.
  8. TechAdmin

    TechAdmin Administrator Staff Member

    We tried to make one but failed at it. Doing so with common parts like a can and soda can. Couldn't get it to take for for whatever reason. Friction seems like the killer.
  9. carnut1100

    carnut1100 Well-Known Member

    Get them designed right and they will produce a fair bit of power.
    There was one in Sweden in the '70s in a Ford Pinto that put out 115hp...
    Little toy size ones need to be almost frictionless to work.
  10. guyfour

    guyfour Registered User

    I just got my sample of a precision dashpot in the mail, it took what seemed like around a week to get here which is pretty good. Now I need to figure out how to make it into a stirling engine. Is there another piston like device in the hot water lid on that one?
  11. carnut1100

    carnut1100 Well-Known Member

    That blue thing you can see in the jar is a styrofoam piston and the stuff wrapped around it is stainless steel mesh to act as a heat exchanger. It is in the inside of the jar and stationary. The styrofoam piston almost touches it and the air it displaces must go through the mesh to move from one end of the jar to the other.
    The white cup contains only hot water and the bottom of the jar is sitting in the water.
    The piston rod going to the blue piston is sealed around where it runs into the jar, but it must be a low friction seal.
    Not sure on what the actual seal is on this engine.

    Hope that helps...
  12. Gordo

    Gordo New Member

    Isn't there a smaller design possible with another "piston" attached to the airpot?
  13. Rooster

    Rooster Member

    0 This site has some info on the Sterling Engine plant on the west coast USA.Phil
  14. NaeKid

    NaeKid YourAdministrator, eh?

    Found a cool video of a guy who built a stirling motor to power a small music-box.

    This would be a nice way to put a child to sleep at night ...