Remember the Apollo 13 attempt where they on had X amount of amps to get back from space?  Until we have a reason to build ONLY most power efficient circuits how will we?   Set a limit of wattage, then ONLY use that wattage to test from and create circuits conforming to the wattage law you set.   Why spend time on a circuit that so many others "power through" only to realize the circuit doesn't meet your needs later?  Need is the mother of invention so I feel this self set limit could save time and give some guidelines to help them stay on track (if there is any).    Many topics seem to relate a common theme that we should define, here is my stab at it:
Nature is a great Jack Benny (KISS) Mr Economy,  we see energy in heaps in collapsing vacuums, IE.. lighting, plasma bursts, spark gaps, etc.. (Fuels)  This energy is more than the cause because the initial vacuum collapsing causes partials to travel at or near light speed and colliding with other radiant partials which builds more energy.  So our need would seem to be to build collection devices for RADIANT energy and filter out of IT the wavelengths (such as current) that we find useful.   The crisper the vacuum is created the faster the collapse of the vacuum, the MORE radiant energy (including electricity).   
Since light has a + and - value   why not focus a beam through (encompass is best) a coil to ENHANCE this collision activity?  Don't forget to collapse the light in time with the coils collapes though, It may be important I feel.  Visable light has a positive value Nick proved with his clear dieelectric tests.    Assumption then our visable light is over half way thru the entire spectrum of wavelengths, otherwise it would be neutral or negative (there is negative value radiant energy of course.... else where do republicians come from      kidding guys ))  )