 Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me. |
Forum Index : Solar : Solar Stirling engines
| Author | Message | ||||
| kamel Newbie  Joined: 07/04/2008 Location: AustraliaPosts: 5 |
Was wondering if anyone had tried anything along the lines of a home made Stirling engine generator with a solar collector. In ideal terms it appears significantly more efficient than a PV system in terms of space, without being quite as complex as a solar steam turbine... and therefore in the realm of the possible for a home made job. There are commercial versions in use that give about 12kw per mount. Was thinking that maybe one could be put together from a 2 - 3 meter satellite dish mosaiced with mirror segments cut to size, a simple "huxtable hot air engine" [but bigger obviously] extended outwards from the dish for heating [to start with]... and a commercial tracking system to keep the dish pointed. This form of the Stirling is probably the least efficient, but simplest... and the shape suits a collector. As an alternative I was thinking of a single, really big fresnel lens such as is found in the back of rear projection TV's. 70cm * 110cm. You can get the focus down to about a cm and is hot enough to melt aluminium, zinc, and destroy other stuff... but if the focus was relaxed just enough match the end of the stirling engine 'hot end' it'd probably work pretty well. Anyway. Ideas? Critiques? Suggestions? **Edit* Hmm, preliminary calculations show about four square meters of reflective area for a 2.3m sat dish. Not sure on how much energy gets lost to mirror absorbtion. A big fresnel lens only gives 1.1 square meters... with a bit of loss due to scattering. An array of 9 x 40 x 30cm lenses gives 1.08 square meters... but loses to both scattering and reflection. |
||||
Gill Senior Member  Joined: 11/11/2006 Location: AustraliaPosts: 669 |
I like the idea of solar power generation being independent of those multinational companies buying up photovoltic crystal production. This Sterling idea gives the DIY'er with home machine shop resources a way of generating Solar power when the environment is not suitable for wind or hydro. But I'll have to add it to my wish list of projects as currently beyond my resources. 
Great idea. Keep us advised of your progress. 
was working fine... til the smoke got out. Cheers Gill _Cairns, FNQ |
||||
tattoomike68 Newbie Joined: 13/04/2008 Location: United StatesPosts: 4 |
Here is a video by GREENPOWERSCIENCE you may have seen. All his videos are good. http://www.youtube.com/watch?v=fUrB7KRvxUk Im sure if you build a small scale working model it will inspire you to go bigger. |
||||
| grub Senior Member Joined: 27/11/2007 Location: AustraliaPosts: 169 |
I can remember seeing on tv quite a few years ago a story of a young girl who made a mirror to reflect sunlight onto a small steam engine. The system apparently worked better than expected. I have also heard of (but not seen) a story of a solar run steam car that competed in an early Solar Race (from NT to SA) and that did quite well also. If one made a sun tracking dish then optimum power would be generated. I would like to see how you progress with this idea too. |
||||
CraziestOzzy Senior Member Joined: 11/07/2008 Location: AustraliaPosts: 135 |
http://www.youtube.com/watch?v=nq6iCO9KLKA http://www.youtube.com/watch?v=ajHGU3Nti6E http://www.youtube.com/watch?v=wEsycEZ7XAY Above are three links I grabbed from my favourites on Youtube...the third link is of a beta engine, which I personally think is the best. They have less moving parts and are simpler to make. It was the stirling engine freezer idea (using the technology in reverse) that gave me the bug to DIY power. What I know of the stirling engine, is that they do not develop enough torque to generate useful electricity when under load from a generator. I could be wrong on this belief though. I think a large stirling engine may overcome issues with torque, but a means of starting motion besides turning the "wheel" by hand will have to be examined (both for large or small engines). http://cr4.globalspec.com/member?u=25757 http://www.instructables.com/member/OzzyRoo/ |
||||
| kamel Newbie Joined: 07/04/2008 Location: AustraliaPosts: 5 |
Yup, I've found a couple of examples of basically exactly what I was looking at doing. All found that you couldn't get enough useful work out of smaller versions. Still wish I could lay hands on one of 5HP engines that were intended for the third world though. Be interesting to experiment. |
||||
| adric22 Regular Member  Joined: 06/08/2008 Location: United StatesPosts: 47 |
I saw something on the news a few years ago showing this idea. They had something that looked like a large satellite dish and inside was a stirling engine and generator. They said it actually created more power per square foot than a photovoltaic. I agree, as for harnessing solar power for the DIY person, this is probably about the only decent way to do it. We just don't have the ability to produce photovoltaic cells in our home. |
||||
vasi Guru  Joined: 23/03/2007 Location: RomaniaPosts: 1697 |
Stirling engines fields Hobbit name: Togo Toadfoot of Frogmorton Elvish name: Mablung Miriel Beyound Arduino Lang |
||||
 Print this page |
