Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
264336 | Energy and Buildings | 2011 | 6 Pages |
The choice of building envelope is critical for the energy performance of buildings. The major part of the energy used by a building during its lifetime is used for maintaining a suitable interior thermal climate under varying exterior conditions. Although exterior heat radiation properties (i.e. total solar reflectivity and long wave thermal emissivity) have been well accepted to have a large impact on the need for active cooling in warmer climate, the effect of a reduced thermal emissivity on interior surfaces on the building thermal energy flux is rarely studied. This paper addresses the sensitivity of the thermal energy flux through a sandwich panel, by systematically varying the surface thermal emissivity (both interior and exterior) and total solar reflectance of exterior surface, for three geographical locations: southern, middle and northern Europe. A model is introduced for calculating the effect of both interior and exterior optical properties of a horizontal roof panel in terms of net energy flux per unit area. The results indicate potential energy saving by the smart choice of optical properties of interior and exterior surfaces.
► Thermal energy flux through a sandwich panel vs. optical properties of coatings. ► Modeling the effect of both interior and exterior optical properties of coatings. ► Potential energy saving by the smart choice of optical properties.