Hi, Till!
This is a subject that I've wondered about, but have never before
investigated. Many years ago I visited New York City, and I asked a
taxicab driver about the steam that rose from grates and manholes. He
laughed and told me that there were dragons in the sewers.
Whenever there is a question regarding why or how something is done,
one of the first places I go for information is the archives of The
Straight Dope. In case they don't have The Straight Dope newspaper
columns in Germany, I'll say that this collection of questions and
answers on a wide variety of subjects is a treasure-trove of trivia,
with a base of genuine wisdom nicely enhanced by wit. The Straight
Dope's mastermind, one Cecil Adams, is billed as "The World's Smartest
Human Being," and I can't dispute that. Cecil's helpers, the Straight
Dope Staff (SDSTAFF,) are no slouches either.
Here is an excerpt from the online archives of The Straight Dope~
Dear Straight Dope:
Growing up in England, I would often watch U.S. TV shows, Starsky and
Hutch for example, where I noticed that steam rose from the streets
during car chases. I have traveled extensively around Europe and
Africa, yet never saw any steam. Imagine my delight when I took my
first trip to the U.S., Denver in fact, and saw steam, not just during
car chases, but all the time! What do people put down there? Please,
tell the world! (We don't have a straight dope over here, not even a
crooked one.) --John Brooks, Buckinghamshire, England
SDSTAFF McCaff and SDSTAFF Manny reply:
Yup, here in the U.S. we've got the Straight Dope, steam rising from
the streets, and Starsky and Hutch. All that a truly progressive
civilization requires.
As for what people put down there that causes steam to rise . . . why,
they put steam, of course. Large steam plants tended to be more
efficient than small ones, and some industries have waste heat, so,
where the density is high enough to support it, you may find
centralized steam plants selling heating steam to their neighbors,
distributing it in underground insulated pipes. This page from the
Website for Con Edison, the energy utility in New York City, explains
how it works:
Steam power is as much a part of Manhattan as subways and Times
Square. The first steam generation plant began operating in 1882 - six
months before the first electric service. From this plant, steam
traveled through a half-mile main to distribute heat and power to the
heart of the downtown Manhattan business district - today's financial
district along Wall Street.
Increased public acceptance and popularity of the steam system came in
1888 when a severe blizzard nearly shut down the city. Buildings with
their own boilers had difficulty obtaining sufficient coal and wood to
keep the building heated. However, the New York steam system remained
in service.
Today, steam power has grown to play a major role in the life of the
city. In fact, the Con Edison system has become the largest steam
district in the United States--larger than the next four U.S. systems
combined.
More than 100 miles of mains and service pipes make up the Con Edison
steam system. The pipes range in size from one to thirty inches in
diameter, and deliver this clean, efficient energy source to about
2,000 customers from the Battery to 96th Street. In fact, Con Edison
steam is so clean and pure that it meets all FDA standards. Thus,
there are no adverse health effects associated with steam use. Steam
can be used for everything from heating and cooling to sterilizing and
food processing.
Not to mention providing a lot of atmosphere (literally) in Taxi
Driver and Starsky and Hutch.
--SDSTAFF McCaff and SDSTAFF Manhattan
Straight Dope Science Advisory Board
The Straight Dope Archives: Cecil's Mailbag
http://www.straightdope.com/mailbag/mstreetsteam.html
Like you, I had assumed that the steam rising from underground was
related to the New York City subway system. Apparently the only
relation is that both the steam system and the subway system are
subterranean conduits, one of which transports steam, and the other
people. The steam vents assist in regulating the pressure of Con Ed's
huge network of pipes and valves, the world's largest steam system.
Here is Con Edison's Web page extolling the virtues of steam power:
Consolidated Edison: Why Steam
http://www.coned.com/steam/whysteam.asp
Thanks for the interesting question. It is good to learn that there is
an explanation for the steam other than dragons. Ever since that
taxicab driver told me the dragon story, I have suspected that he was
taking advantage of my gullible nature as a tourist.
My search strategy, as mentioned above, consisted of visiting The
Straight Dope site, where I did an archive search using the keyword
"steam." I also went directly to Con Ed's site to learn more about the
uses of steam power in New York City.
If you need anything further from me on this subject, just vent! ;-)
Best wishes,
pinkfreud |