Find a book on passive solar heating of houses, and in it, a table of solar heat gains for your area. For windows facing each of the four directions of the compass, plot a curve that represents the solar heat coming through a square foot of clear glass on an average day in each month of the year. Which window orientation maximizes wintertime heat and minimizes summertime heat? Is there an undesirable orientation that maximizes summertime heat and minimizes wintertime heat?