Date: Sat, 15 Jan 2000 9:02:21 +0000 From: <mrwu@cello.qnet.com> (Howard J. Wu L.Ac) To: cp@opus.hpl.hp.com Message-Id: <aabcdefg135$foo@default> Subject: Re: Solar Power Fans
I once meet someone would wasn't worried about nuclear winter. He said we
could grow ethanol under electric lights which of course would be powered
by generators using some of the ethanol we made. I had to explain the
absurditiy of this propose, some theory called the conservation of energy.
In regards to solar power fans, I doubt this would be a practical
idea. Concider that the amount of engery needed to move enough air to be
of benifit would be far greater than the amount of sunlight striking the
greenhouse. Else air convention from sunlight on the greenhouse would
generate enough wind to do the job without any mechanism. Add to this that
good solar cells are about 11% efficient, (fans motors are around %90 at
best.) I suppose one could buy a large field of solar cells, personally
I'd get the cord.
There are passive systems that might be of use: Phase change vents that
open at a set temperture. Evaporator cooling towers. Even high tech (or
low tech) shading of the greenhouse.
Howard J. Wu
Bishop Ca.
mrwu@qnet.com
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