FED vs thermal energy

FED

noun

  • Field emission display. 

name

  • Federal Reserve System. Alternative spelling of Fed 

thermal energy

noun

  • The energy released by an explosion 

  • A form of energy; sensible energy; heat 

  • The internal energy of a system in thermodynamic equilibrium due to its temperature 

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