Backyard Aquaponics - Home Aquaponics - Commercial Aquaponics
|Greenhouse Solar Heat Storage|
For solar aquaponic greenhouses to remain warm during cool nights or on cloudy days, solar heat that enters on sunny days must be stored within the greenhouse for later use. The most common method for storing solar energy is to place rocks, concrete, or water in direct line with the sunlight to absorb its heat.
Brick or concrete-filled cinder block walls at the back (north side) of the greenhouse can also provide heat storage. However, only the outer four inches of thickness of this storage material effectively absorbs heat. Medium to dark-colored ceramic tile flooring can also provide some heat storage. Walls not used for heat absorption should be light colored or reflective to direct heat and light back into the greenhouse and to provide a more even distribution of light for the plants.
The amount of heat storage material required depends on your location. If you live in southern or mid-latitude locations, you will need at least 2 gallons of water or 80 pounds of rocks to store the heat transmitted through each square foot of glazing. If you live in the northern states, you will need 5 gallons or more of water to absorb the heat that enters through each square foot of glazing. Approximately three square feet of four-inch thick brick or cinder block wall is required for each square foot of south-facing glass.
The amount of heat-storage material required also depends on whether you intend to use your solar greenhouse for extending the growing season, or whether you want to grow plants in it year-round. For season extension in cold climates, you will need 2 ½ gallons of water per square foot of glazing, or about half of what you would need for year-round production.
This information is courtesy of ATTRA - National Sustainable Agriculture Information Service