Optimal Financial Insulation Thickness of a Broiler House
Keywords:broiler house, optimum insulation thickness, cooling load, heating load, NPV, Greece
A common method for environmental control in livestock facilities is to use thermal insulation for exterior walls and roof. In regions with cool winters increasing the insulation thickness decreases the heating requirements, however in regions with hot summers may lead to unwanted increase of inside temperature, thus intensifying cooling loads. It is worth noting that financial thickness optimization of a broiler house external walls and gable roofs insulation for different orientations has not been sufficiently addressed, thus a detailed transient simulation was used to model existing energy audited broiler house and to calculate its annual heating and cooling loads. For that, hourly climatic data and all the heat and moisture gains and losses resulting from birds, heat flow through the building envelope and ventilation were taken into account. An economic analysis based on the Life Cycle Savings (LCS) method was performed for the walls and gable roofs for various insulation thicknesses and orientations. The comparison of the annual heating load per unit area with that of similar energy audited broiler houses was satisfactory. The optimum insulation thickness of external walls and gable roofs was found to be between 4.0 cm and 4.5 cm depending on their orientation, while the wall facing north offered the greatest economic benefit compared to other orientations. According to the results, the annual cooling load was 3.3 times higher than that of heating.