Heat Sources & Grades of Waste Heat

Every site that burns fuel or runs machinery throws heat away, and a large fraction of it is warm enough to be useful. A typical industrial facility loses 20 to 30% of its fuel input as waste heat up flues, off condensers, and out of exhausts. Recovering it is nearly free energy, but only if the heat is the right temperature, arrives when it is needed, and has somewhere to go. This opening lesson sorts waste heat by its two properties that decide its value, temperature and timing, and sets up the matching problem that every project in the course turns on.