How does a greenhouse work?

        Some of you may wonder how a green house takes solar energy and turns it into thermal energy.  A good example of  this is something you can observe every day in the summer in you own car.  It happens when you leave you car in a sunny parking lot with the windows up.  The solar energy is passing through the glass and is heating the cars interior.  Whats really happening is the short wave infrared waves are going in and are turning into long wave infrared waves, which cannot escape. So the just reflect around and get absorbed by their supproundings.  This of course is the ideal setup to grow plants. And thus you green house helps your plant grow.

  This illustration shows how the glass wont let the long wave radiation out.

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        The infrared light waves are invisible to the naked eye, they lie between microwaves and visible light waves in the light spectrum.  Other waves include UV, and opaque. We all know all about infrared, we may just not know it.  Its what you feel when you stand next to a fire, its lying in the sun and sweating, or huddling up for warmth.

        Light waves are measured in "Nanometers".  UV waves are measured from about 300-400 Nanometers, visible light waves measure about 400-700, The infrared measure at about 700-3500.  The Opaque range in the low end at 300-400, and at the high ent at about 2000-3500.

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         Harvest the Sun  By:  Nick Nicholson

Page by:  Casey levit