solar cooling

The solar optical properties of micro- and meso-porous materials that can be building integrated or roof added for evaporating cooling purposes were studied and compared with conventional building materials. The results are interpreted in correlation with their water absorption capacity. For further studying their solar optical properties, absorbance measurements were solar-weighted in accordance with the ASTM G173 standard. Mesoporous materials presented high irradiation absorbance in the IR spectrum with significant variation depending on the water loading at different relative humidity.

The principle of roofs cooling through the water vapour adsorption-desorption cycle in porous materials is presented. In order to study the effect, porous materials of natural origin or synthesized at our lab, were characterized at the micro-scale with SEM, XRD, UV-VIS-NIR spectrometry, thermal and water-vapour adsorption measurements and tested at the urban scale in a wind tunnel of controlled environmental conditions and simulated sun.

This paper provides experimental results derived through field testing of a partial load solar energized cooling system in Madrid during the summer period of 2003. Solar hot water was delivered by means of a 50 m2 array of flat-plate collectors to drive a single-effect (LiBr/H2O) absorption chiller of 35 kW nominal cooling capacity. Thermal energy was stored in a 2 m3 stratified hot water storage tank during hours of bright sunshine.

The use of heat produced by solar thermal collectors is an interesting option for thermal driven airconditioning process. Three technologies are commercially available: absorption, adsorption anddesiccant cooling systems. This paper is focused on solar desiccant cooling and solar absorptionsystems. The aim of the study is to assess energetic and comfort performances of these solar coolingsystems integrated in an office building.