Re: [Phys-l] cooling hints

[James Mackey <jmackey@harding.edu>]

Years ago, during 70s energy crisis (la plus sa change, la meme la chose!) I
did a simulation in lab with a variac and a homemade AC box that was
connected to a simple immersion heater placed in a an insulated beaker and
an uninsulated beaker.  Part of the lab was to compare energy consumption
between complete AC turn off and reducing the set point temperature.  A
complete cycle was run to simulate a constant AC setting, a temp reduction
setting and a complete AC off by starting all runs at a fixed temperature
and running through the 3 cycles for fixed times and then returning to the
initial temperature.  Invariably, minimum energy consumption for the
complete cycle was lowest with the  complete turn off cycle.  Probably not
terribly applicable to today's units, but students found it very
surprising.  Most students believed you used more energy to "catch up" if
you turned off the heater.
James Mackey

On Wed, Aug 24, 2011 at 3:31 PM, John Clement <clement@hal-pc.org> wrote:

> I know someone who was working for the Army and in the winter they used to
> open the windows to combat the overheating of their work space.  But during
> one year when there was a jump in energy prices the Army sealed the windows
> shut to prevent this.  Why they didn't just turn down the heat is an
> unsolved mystery.  So the employees found they could have comfort by
> turning
> on the AC.
>
> John M. Clement
> Houston, TX
>
> > Ah! Bitten by the "Law" of Unintended Consequences.
>
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