Abstract: A temperature control system for greenhouses based on the accumulation of energy by means of providing water or any other liquid in reservoirs located either in the lower part of the greenhouse, in which case a raised floor below the cultivation level is necessary, or else in an accumulation reservoir consisting of a tank located outside the greenhouse. The liquid from the corresponding reservoir is circulated through the greenhouse by means of a heat exchange system, being able to heat/cool the air circulating therethrough and such air will in turn heat or cool the greenhouse.