Science & TechMental model
More energy out than in? Look for the hidden source.
Two laws of thermodynamics have never been broken: energy does not arise from nothing, and heat flows by itself only from hot to cold. That is why the US Patent Office demands a working model for 'perpetual motion' applications. Many supposed miracle machines really do run, just on an invisible source: barometric swings, temperature differences, a hidden battery.
Useful: With every 'free energy' offer, the first question is: where does the energy really come from?
Source: en.wikipedia.org