Here’s my latest Solar PSA on how a south-facing window is already a solar collector:

http://www.youtube.com/v/FdGAd…

“Any window that sees direct sunlight is a solar collector.  You can learn how to use that free energy to make your home more comfortable and secure.  Caulk and seal the window against drafts.  Install storm windows on the exterior, interior, or both.  Cover the window at night with an insulating curtain to prevent conduction, convection, and radiative heat loss.  A valence above the window will stop night-time drafts and reduce condensation.  A sunny window can double as a greenhouse for starting seedlings or growing house plants.  Expand the solar space below, above, or beside the window with a windowbox solar air or water heater.    You can even design a living system to provide fresh vegetables and fish year round while producing space heat, cleaning the air, and reducing waste.  A south-facing window is already a solar collector.  Learn how to use it.”