“Follow the energy flow in all its guises from input till output. You will never fail to analyse any system no matter how complex it may be” – probably the most insightful piece of advice I was ever given.
When we are asked which is the best way to analyse a system, and not just for energy management, our approach follows this advice and typically our answer is: take the energy perspective. Think energy.
What does this mean? It starts and ends with the Law of Conservation of Energy, a.k.a. the First Law of Thermodynamics, which basically states that energy can neither be created nor destroyed in an isolated system. An isolated system is one where neither energy nor matter, which are intimately interlinked can be exchanged between the system and the surroundings.
Energy thinking has a transcendental twist to it, as it transcends the system under analysis, or its constituent parts. The energy perspective allows the analyst to equate the energy equations describing the system and its constituent parts. These equations could represent heat, mechanical, electrical, nuclear, whatever source of energy. As a first approximation, consider the system to be 100% efficient, which allows the various energy equations to be directly equated. Losses will ensue but as a first approximation, this approach suffices.
Additionally, energy thinking has an intuitive element to it, as it follows a trail which is shared by all systems which have the ability to do work (the very definition of energy). So, equating the energy stored in a battery with the energy stored in a stone drawn by a motor results in equating the energy provided by the accumulator to the rotational energy provided by the motor and finally the potential energy gained by the stone.
When stuck for a solution, you can do worse than to Think Energy. Try it, and share with us your success stories.
