A practical example for the mass calculation of a evaporation plant is given and the mass calculations made by hand and computer are compared and the results are satisfactory.

When it is short of water, a plant, which normally USES evaporation as a means of cooling, cannot rid itself of the heat it absorbs from sunlight or the heat that may build up from its own metabolism.

When it is short of water, a plant normally USES evaporation as a means of cooling.