​Waste is a man-made concept.  In Nature outside of man, there is no waste. Evolutionary brilliance ensures that the waste from one organism will be utilized at high value to another organism.  Waste in our chemical and material world is simply a material or energy for which a valuable use has not been discovered or implemented.  While we will never defeat thermodynamics in attaining perfect cycles and entropy will always win, the cycles and systems that can be constructed can strive to continuously move toward the perfect goal of zero waste.