This paper analyzes, during a typical coldestday of the year, the evolution of the daily energy needed to maintain fixed, a set temperature inside a Direct Solar Dryer (DSD). Two parameters areconsidered to study the response of the dryer equipped with an auxiliary heating system:1- The Local climatic conditions,2-The geometric shape of its DSD. In order to examine the influence of climate type on energy variation, three Moroccan sites have been selected, namely Rabat (latitude 34°00’ N), Tetouan (latitude 35°34'N) and Fez (latitude 34°02'N). For the dryer geometric shape impact, several dryer dimensions are scrutinizedusing different set point temperatures