electrical energy vs power supply

electrical energy

noun
  • Energy made available for consumption or consumed in the form of electricity or electric power; electricity. 

power supply

noun
  • A source of power such as the mains or a generator. 

  • That part of a piece of electronic apparatus that provides appropriate voltages for the rest of the electronics from the connected AC source. 

  • Used other than figuratively or idiomatically: see power, supply. 

How often have the words electrical energy and power supply occurred in a corpus of books? (source: Google Ngram Viewer )