This 3D-Printed Thermoacoustic Stirling Engine Now Runs on Biogas from Your Own Plant

An open-source hardware enthusiast known as has released a significantly improved version of his thermoacoustic Stirling engine, now fully 3D-printable — including the burner and hot end, which are designed for SLA metal printing.

We previously covered the original open-source engine, but the latest iteration brings a major upgrade: a biogas/methane burner is now integrated directly into the 3D-printable hotend. This design allows for a heat exchange geometry that would be extremely difficult to achieve with conventional manufacturing methods. The engine itself is a thermoacoustic type, which means it has only one moving part at the output shaft — making it highly efficient and inherently safe, with no risk of boiler explosion.

All design files are available under an open-source license at OwnEnergy.org. The site provides links to the project's Discord channel and a newly launched old-style forum for collaborative development. It has also become the central repository for data and discussions about 's homescale biogas plant, which serves as the fuel source for this little engine.

The developer notes that if you prefer a conventional combustion engine, you can 3D-print one too, but it will require more "vitamins" (additional non-printed parts) than this Stirling unit needs. The project aims to make decentralized energy generation accessible to hobbyists and off-grid enthusiasts.