Home Built Useful Solar Stirling
Stirling Engine discussion/design for the homebuilder/DIY'er. In the 1980's McDonnell Douglas (now Boeing) built a solar concentrator and Stirling engine combination to generate electricity from the sun.
"In 1996, SES acquired the patent, tooling, and equipment rights to the world's most efficient solar dish concentrator system: the Dish Stirling. Initially developed in the 1980s by McDonnell Douglas (now The Boeing Co.) the Dish Stirling system was field-tested by Southern California Edison and Georgia Power for over 175,000 hours between 1982 and 1988. Edison's test data indicated the Dish Stirling out-performed all other solar-to-electric generating systems by a factor of two, yet had comparable start-up costs. SES optimized the McDonnell Douglas dish to operate with a 25kW Stirling power conversion unit (PCU) developed in Sweden by United Stirling, Kockums and Volvo. The resulting system, the "Dish Stirling", has fewer moving parts than comparable diesel engines and operates relatively quietly. The SES Solar Test Site and related tooling and equipment facilities are located at the Boeing facility in Huntington Beach, California. The 25kW SES Dish Stirling system has an operating track record of more than 17 years. Since 1984, it has held the world record for efficiency in converting solar energy into grid-quality electricity."
Since most people don't have room for a 37' diameter dish, as well as a 25KW generator the question arises, can this principle or another utilizing Stirling technology be downsized for the individual to build their own scaled down unit for practical power generation for their own backyard. Photovoltaic's are expensive, and isn't something the vast majority of DIY'ers people can build. Sterling engines can be built and thus a reasonable approach for the "homemade" population and coupled with a PMG, permanent magnent generator. PMG's can be built by the DIY'er. One of the most popular and freely documented is Hugh Piggott's PMG design.
I've started this Wiki, in hopes to find people interested in creating a useful but scaled down system to design/develop such a home system. Their are a number of resources on the web for alternate energy and home power generation especially PV and wind generation.
Some links: What is a Sterling . An installation of a solar concentrator and Stirling in France and I mean Large French Installation! Some commercial Stirlings: Solo's Commercial Stirling ,Stirling Thermal Generators.
Here is a link that has plans for a tin can walking beam stirling. A flat plate Stirling . An excellent example of a free piston Stirling. A Tin Can Stirling. This site has great animations for the beginner. The Stirling WebRing . A nice site Stirling Sudy Group. A website used for ME college project. A very interesting solar power diaphragm Stirling.
If you are going to concentrate solar energy, you will need to track the sun. To do that you need either tabular data for your location for sun position vs calender vs time or a solar tracker. For the DIY'er a home built solar tracker might be part of the total system solution. A Solar concentratorconcentrates sunlight into a small area to generate elevated temperatures. Fresnel lenses are also being used as solar concentrators. Some DIY'er are even pretty intense about their Solar Tracking Concentrators.
Building a parabolic concentrator is not a difficult feat for the average DIY'er. One site has
a simple technique for the fabrication of parabolic reflectorsand anotherinstructions for making big parabolic concentrators have details including an Excel spreadsheet for calculations.
Stirlings come in many configurations such as this moving cylinderStirling.
This site has a number of approaches including Stirlings to pump water, etc in remote locations.
Heat engines utilize a cycle of heating and cooling to generate power. The most efficient cycle is considered the Carnot cycle. The Beale Numberis an important, empirically derived figure relating the power output of a Stirling engine to working gas pressure, operating frequency, and piston displacement. This theory is based on the isothermal expansion and compression of an ideal gas. TheSchmidt Theoryis a method of calculations for Stirling engines. It is one basis for a starting point in Stirling Engine Design.
Feel free to create a user account and add/edit pages to help this project/vision grow. If you can participate in a blog or bulletin board, you will find using a Wiki is just as easy. The results however are more readable than a bulletin board or blog. You will see at the top tabs: discussion :edit :watch...etc. By choosing the edit tab you will be able to edit this text. When you get to the edit page just type, delete, copy, paste like any text editor. You will also notice a button bar at the top of the text box that allows you to insert images, hyperlinks, change font among others.
A nice Stirling site.
A set of plans for a Stirling.
Another nice link Sunpower
More design info sesusa