Vakuum-engine, flame-eater
The manufacturing, assembling and tuning of this engine was the main part of my final thesis in high school. An other part of the thesis was to measure and tune its performance. The biggest challange is to get this kind of machine run due to its extremely low effectiveness.
The measured power of my vacuum-engine back then was around 0.000196 hp or more scientific 0.144 Watt with an effectiveness of 0.097%.
My final high school thesis is available under Vacuum-engine, analysis and tuning and how a vacuum-engine works in general is explained under Functioning of a vacuum-engine