Hot Water

To the Editors:

Stein Weissenberger’s attack [NYR, March 12] on my book, The Economy of Cities, raised a point with which Richard Sennett did not deal in his reply: the presumed naïveté of my suggestion that thermal pollution of rivers by power plants could be eliminated, with economy, if the heated water were usefully recycled. In Oregon, simulated use of just such water for warming soil underground demonstrates that (a) vegetables which must now be imported from California and other southern points could be grown close to the point of consumption instead and (b) yields of many crops now being grown in Oregon can be doubled without nearly doubling the work. Fuel savings are obvious: i.e., in transport and in farm work. Other possibilities suggest themselves: for instance, use of the piped heated water to keep roads clear of snow. Warmed pavements are not unknown, although when they do not take advantage of an otherwise wasted by-product they are expensive. The by-product would save fuel directly and also indirectly by reducing use of snowplows. The principle is that energy used instead of wasted does save energy.

Now, about the second law of thermodynamics: To be sure, one cannot use heated water to obtain a higher temperature than that of the water itself. Since heated water from power plants is not as hot as would be required for, say, the heating system of a building, it is inappropriate to try to heat buildings with it. But there are other appropriate uses. An unimaginative engineer who reviewed my book in the Saturday Review, evidently thinking of heating buildings, jeered at my “violation” of the second law of thermodynamics. I have been fascinated, since, to observe this comment becoming gospel (Mr. Weissenberger is not the first to have seized upon it). I am no physicist, but I do have ready access to a physicist who kindly read my manuscript to protect me and my readers from error, and I advise Mr. Weissenberger to take similar precautions instead of parroting a casual error in a book review. His accusation that I am self-confident, I accept; but his desire to show that this trait is “characteristically” combined with naïveté requires that he find different evidence.

Jane Jacobs

Toronto, Canada