Can't vouch for your ancient machine or text editor, but writing and compiling on a modern machine with intellisense, the editor uses a lot more energy than the browser
This paper didn't seem to deal specifically with compilers, editors, browsers, or intellisense. But I'm curious what counts as "modern" -- how often should I replace my personal machine, or what should its specs be, so people like you don't call it "ancient"? (I already know that I should be using LightTable or Atom or IntelliJ to be "modern" in terms of editors.)
https://www.cs.virginia.edu/~weimer/p/weimer-asplos2014.pdf