My latest engine is a mostly 3D printed Stirling engine. Although I'm not running it on solar power, it could be easily made to do so. The design is open source so you can get all the drawings, CAD files, and other information to make one. The information starts here:
Linear guides are one of the most important components required for the design of automated or computer-controlled equipment. Aluminum profile extrusions, used for these guides, can enable designed-in functional features.
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