letters to the editor

Operation
Swamp
Cooler
Story & Photos by Calef Letorney
Swamp coolers evaporate water, cooling the air much like air conditioning.
I was 19 when I first learned of swamp coolers. My late introduction
is due to the fact that I grew up in the relatively humid climate
of Vermont and swamp coolers function best in dry climates. Right
away I was intrigued by the low energy consumption and relative simplicity
of the swamp cooler: All you need is air flowing through a
damp cloth. This simplicity saved the day during a heat wave last July
on a road trip from Vermont to Utah, when I decided to fashion a
swamp cooler of sorts; evaporative cooling made all the difference
and so I am sharing my discovery to cool fellow A/C-less Rover owners
in hot dry places everywhere.
My buddy Buck and I had just crossed the Colorado Rockies
headed towards Salt Lake City on I-70. Like many Rovers, mine lacks
A/C and so I prefer to relax in the shade of a swimming hole by day
and drive at night, but chances had us stopping to see a friend in
Moab in the oppressive mid day heat. On this particularly cloudless
day, my TDI Defender resembled a convection oven and I desired A/C
oh so badly. Seeing as proper A/C was out of the question, Buck and
I got to thinking of using evaporative cooling to slow our melting.
After all, we had plenty of fast moving dry air and gallons of water to
evaporate. In essence we wanted to create a swamp cooler inside my
Rover.
Upon conceiving the idea of a swamp-cooled Rover, I
immediately imagined a tank of water above the windscreen with a
drip feed down to a wicking material behind my dash vents. In fact,
Buck is a mechanical engineering student (which I understand is bit
of a rarity for someone named “Buck”) and so we kicked the design
idea around a bit. Granted, this design could create a bit of a wet
mess in the dash area, but it couldn’t be any worse than the healthy
amount of water ingression through my dash vents in a hard rain. The
idea seemed promising so we even called a few Rover gurus to share
the genius and the idea was well received. In the end we concluded
that the project had promise but it wasn’t going to keep us from
expiring in the near future.
It was time for immediate action. Buck held the wheel (I-70 is
mind-numbingly straight and deserted at this point) while I took my
shirt off. Buck then emptied his water bottle onto my shirt and stuffed
it into the mesh behind my open dash vent then repeated with his shirt
in the passenger vent. We closed all the windows so the only air
coming in was through our cooler and waited patiently… for maybe
ten minutes. While the idea had promise it was ultimately considered
a failure due to the seemingly slow or non-existent cooling effect.
Unwillingness to wait was fostered not only by the increased heat from
closing windows but also the uncomfortable sticky sensation of hot
vinyl seats our bare backs. We proceeded to try several variations of
opening and closing door windows, sunroof and side windows, all to
no avail. And so the experiment was canned and Buck held the wheel
again while I put my shirt back on.
While ultimately a failure, the experiment was encouraging
because I enjoyed a few cool minutes as the last of the water
evaporated from my shirts and we learned much.
It seemed airflow was all-important; when the windows were
closed the cabin really turned into a sauna. It seemed the dash vents
failed due to lack of airflow and so a new plan was hatched: we would
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