machinery vs power source

machinery

noun
  • The machines constituting a production apparatus, in a plant etc., collectively. 

  • The collective parts of something which allow it to function. 

  • The working parts of a machine as a group. 

  • The literary devices used in a work, notably for dramatic effect 

power source

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

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