Every human being, no matter what he is doing, gives off body heat. The usual problem is how to dispose of it. But the designers of the Johnstown campus of the University of Pittsburgh set themselves the opposite problem--how to collect body heat. They have designed a collection system which utilizes not only body heat, but also the heat given off by such objects as light bulbs and refrigerators as well. The system works so well that no conventional fuel is needed to make the campus’s six buildings comfortable,
Some parts of most modern buildings--theaters and offices as well as classrooms--are more than amply heated by people and lights and sometimes must be air-conditioned even in winter. The technique of saving heat and redistributing it is called"heat recovery."A few modern buildings recover heat, but the University’s system is the first to recover heat from some buildings and re-use it in others.
Along the way, Pitt has learned a great d
A. The heat is supplied by human bodies only.
B. The heat is supplied by both human bodies and other heat-emitting objects.
C. The heat is supplied by both human bodies and conventional fuel.
D. The heat is supplied by human bodies, other heat-emitting objects, and conventional fuel.
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