|MLA Citation:||Bloomfield, Louis A. "Question 1119"|
How Everything Works 20 Jul 2018. 20 Jul 2018 <http://howeverythingworks.org/print1.php?QNum=1119>.
Unfortunately, most practical heat engines work best when the hotter object is really hot. For example, a steam engine works best when the hotter object is hot enough to produce very high temperature, high pressure steam. To operate a steam engine with outside air as the hotter object and cold ice as the colder object, the steam engine would have to operate at very low pressure. In fact, it would operate well below atmospheric pressure in a carefully sealed environment. Steam might not even be the best choice for a working fluid—you might do better with a refrigerant such as the various Freon replacements. In effect, your heat engine would be an air conditioner run backward—providing electric power rather than consuming it. Although this could be done, it would probably not be cost effective. The heat exchangers needed to obtain heat from the air and to deliver most of that heat to the glacier, as well as all the machinery of the heat engine itself, would probably make the electricity you generated too expensive. Just because something can be done doesn't mean that it's worth doing. Until other sources of energy become more expensive, this one won't pay for itself.