The optimization of the thermal insulation in the heating and cooling residences

In the countries, which supply the most of their energy necessity from abroad, using the energy effectively and providing maximum energy saving is needed. A rate about 40% of energy sources are used as heating energy and more as cooling energy in some provinces. So to reduce the required energy for heating and cooling of the buildings they need to be insulated, and to be thrifty or sparing. In this study the optimum insulation thickness is obtained by considering the interest and inflation rates, the total heat transfer coefficient, the annual heating and cooling periods, the environment temperatures, the calorific value of the used energy, the costs of the used energy, of the boiler, the radiator, the air conditioner and their types and by reducing the total annual cost to minimum. After that for four various types of energy (coal, natural gas, fuel oil, electricity) in four different provinces (Antalya, Istanbul, Konya, Sivas) situated in different regions, by using two kinds of insulation (expanded polystyrene and rock wool) the optimum insulation thickness, the total annual insulated and un-insulated cost, the energy saving and payback periods are calculated and charts are drawn on two various wall types for each parameter separately. When the results are matched, it is proved that minimum insulation thickness is obtained in Antalya when coal is used as energy source and rock wool as insulation material; maximum insulation thickness and energy saving are obtained in Sivas when electricity is used as energy source and expanded polystyrene as insulation material; minimum investment cost is obtained in Antalya when coal is used as energy source and expanded polystyrene as insulation material, and the shortest payback period is obtained in Sivas when electricity is used as energy source and expanded polystyrene as insulation material for central insulated wall type. Keywords: Thermal insulation, energy saving, buildings, insulation thickness, optimization.