Not Spaghetti

My criticism of various claims about "Combined Heat and Power" (CHP) or cogeneration systems was something I had thought I could keep brief, since the issue was intuitively clear to me. But explaining my understanding of the subject in straightforward non-scientific language has proven trickier than I'd expected. This post constitutes part 2, and will cover problems with many claims of "efficiency" in heating systems; part 3 will be more specifically focused on the several different types of CHP, what is good about them, and what is frequently over-hyped.