This depends entirely on the type of transformation of energy that is taking place, mechanical to thermal, thermal to mechanical, etc. But energy is always conserved, although it may take a different form.
Explanation:
In physics, the law of conservation of energy declares that the entire energy of an isolated system continues uninterrupted, it is said to be maintained over time. This law suggests that energy can not be created either destroyed; preferably, it can only be converted or assigned from one form to another. According to the law of conservation of energy, energy cannot be created or destroyed. So the total value of energy is the equivalent before and after any conversion.
