A perpetual motion machine should conserve all energy in the system perfectly. If it created more than was put in that would both violate the law of conservation of energy and result in a system with increasing energy. The principle of a system that conserves all energy doesn't violate the law of conservation of energy.
err just consume less
'All things are subject to interpretation; whichever interpretation prevails at a given time is a function of power and not truth.' - Nietzsche
Again proving that all of life's problems will be solved in the future.