solar studies

I spent some "virtual quality time" on my new back deck this evening taking a looking at how the sun is working with the back overhang - modeled the southern glass exposure to fine tune overhang dimensions.  The goal is to set your overhang so you maximize solar radiation through the glass in the winter months, and minimize solar radiation in the summer months.  The first model (taken from the deck on the south side of the house and looking west) is at the winter solistice (december 21st at 12:00 noon) when the sun is lowest in the sky.  Notice the deep penetration of sunlight into the living space.  This helps decrease heating load during the winter months.

This next model is at the equinox (march 21st at 12:00 noon).  notice the sun about equidistant between the top and bottom of the glass.

The last model is at the summer solstice (june 21st at 12:00 noon).  The sun will never be higher in the sky than at this time.  Notice the complete shading of the glass by the overhang.