A greenhouse is a glass house sealed to keep air in but made of glass allow sunlight in. This sunlight contributes to the heat in the greenhouse by warming the ground or other material in the greenhouse, and of course the light energy is used by the plants. But the point of a greenhouse is to keep air that is warmed, by the sun and/or heaters that may be required in the greenhouse, from wafting away.
Read the rest of this post... | Read the comments on this post...
More...