The energy use in the building sector for space heating, cooling and water heating, in the European Union Based, reaches the level of on 40% of the total used energy. The building sector is the biggest user of energy, having surpassed the transportation and industry sectors. Additionally, the energy transformation processes and the use of energy are responsible for 94% of the total emissions of CO2, with 45% coming from the building sector. The applicability of solar cooling in Greece was investigated in a medical centre in Igoumenitsa. The use of thermal solar system in the medical centre creates significant environmental benefits in the area of climate change with the reduction of CO2 emissions. The investment cost of such a solar thermal system (70kW, AB absorption technology and a collector area of 291m2) reaches the level of 600€/m2 of solar collector area.