INFLUENCE OF THERMAL STORAGE EFFECTS OF THE SOIL ON GREENHOUSE HEAT CONSUMPTION
Simple formulations to determine the heat demand (e.g. Damrath, 1980) do not contain heat storing elements in the energy balance of the greenhouse so that the heat delivery from the soil is not considered.
In order to examine the influence of storing elements on the heat demand of a greenhouse the greenhouse soil was described mathematically as a heat accumulator and integrated into the equation of energy balance of the greenhouse by means of a heat flux from the soil.
Comparing the calculations showed that the heat delivery from the greenhouse soil leads to a considerable reduction of the heat demand and must not be neglected in case of low heating set points.