• the evenings, stored energy will be radiated into the living space to keep the temperature constant. 

A major point to note to ensure that passive solar design does not over-heat the interior is to balance solar collector areas like windows with floor or wall thermal storage and buffering masses. An imbalance will reflect the greenhouse effect: hot in the day and very cold during the night. An experienced architect or contractor can assist in calculating the amount of heat loss in your home, as can a home inspection auditor if he is able to perform an air leakage test.

Thus, you can determine the annual percentage of heating load to gather with your solar system. It would be a shame not to utilize the sun's free 1000W of energy for every square foot of window area!