Life cycle cost assessment for thermal insulation of above-ground spherical container with different capacities in hot fluid storage processes

Abstract

Due to environmental and economic reasons, thermal energy saving has gained more importance especially in industry. This study is concerned with the application of insulation to improve thermal energy storage in spherical shaped containers positioned high above the ground. For this purpose, the thickness of the insulation applied to spherical containers of different diameters was optimized for convection and radiation heat transfer using life cycle cost analysis. In Turkey, the mechanism of storing the thermal energy of water at different temperatures in four different climatic conditions in Turkey (Ankara, Antalya, Erzurum, and Istanbul) in a container has been investigated. The results of the study show that the optimum insulation thickness and energy savings rise as the water storage temperature and the diameter of the container increase. While there is a 46% increase in the optimum insulation thickness for the vessel diameter from 0.5m to 3m in 20 °C water, a 69% increase is achieved in 100 °C water. Similarly, 85% and 114% increases were found for the optimum insulation thickness from 20 °C to 100 °C for 0.5m and 3m, respectively. In climates with the lowest heating degree-hours (Antalya), the highest energy savings are achieved with the lowest insulation thickness. To accurately determine seasonal storage heat load, a revised heating degree-hour method using hourly solar-air temperature data is recommended. This provides a 13% increase in energy savings.