Sunworks Solar Greenhouse
Paul Shippee, Designer

This attached solar greenhouse is designed for the Rocky Mountain (8,000 Degree Day) climate. It provides about 100,000 BTUs per day to help heat the house, as well as the 300 sq. ft. of floor space for growing plants. It is a 2X6 wood frame structure with a large glass facade (210 sq. ft.) aimed at the winter sun. The glass is insulated at night by a Beadwall system to help maintain minimum air temperatures of 55F degrees.

A small fan moves hot air out of the greenhouse and into the main house delivering heat and humidity on clear winter days. The fan is necessary to prevent temperatures in the greenhouse from climbing over 90F at mid-day. Barrels of water stacked two high along the north wall for thermal storage rise about 15F degrees on a sunny day. They store heat for night time use, preventing daytime overheating.

Glass is tilted 58 degrees to the horizontal to gain maximum solar aperture at this site. It has to be shaded by exterior curtains is the summer. The 350 cfm fan brings heat in winter to the house, dropping 15F before it returns to the greenhouse through an existing door. Summer ventilation is by roof ventilator and by cross-breeze through doors.

Optional Water Heater

The simplest form of solar water heater (a tank placed in the sunlight) is augmented by a simple reflector as shown. The bright foil-clad reflector held by an aluminum frame lights the back of the tank when positioned properly each month.