Force is a directed physical quantity playing a major role in mechanical systems. It can accelerate or deform objects, it can be used to do work or change an object's energy.
When it comes to using energy sources, the most "precious" form is applied – electric current. The basic consideration in this respect is to assess how and in which form it can be generated, produced or "harvested".
"Residual energy" resulting from the electricity generation process (mostly in the form of heat) can then be used further.


