The heat island effect is becoming increasingly more intense in urban areas causing thermal discomfort, increased energy demand and accelerating the formation of harmful smog. The mitigation of the heat island effect can be achieved by the use of cool materials. Cool materials are characterized by high solar reflectance and infrared emittance values. In the framework of this study, the performance of prototype cool colored coatings, developed at the National and Kapodistrian University of Athens, using near infrared reflective color pigments is reported, in comparison to color-matched, conventionally pigmented coatings. The solar spectral properties and the infrared emittance were measured and the surface temperature of the tested coatings applied on concrete tiles was monitored, using surface temperature sensors and a data logging system. The experimental results indicate significant success in developing cool colored coatings. It was found that all the coatings containing infrared reflective pigments have higher solar reflectance values and lower surface temperatures than those of the standard coatings. Cool colored coatings can be used on buildings (roofs and walls) and other surfaces of the urban environment or they can be used to manufacture other cool colored building materials. Furthermore, this paper presents the results of a modelling study, undertaken for the case of Athens, Greece, that attempts to asses the impact of large scale increases in surface albedo, resulting from the use of cool materials, on the ambient temperature. The results of this study can help to promote the adoption of high albedo measures (the use of cool materials) in building energy codes and urban planning regulations.
Synnefa, A., A. Dandou, M. Santamouris, and . Tombrou. International Workshop on Energy Performance and Environmental 1 Quality of Buildings, “Cool colored coatings for passive cooling of cities.” Last modified July, 2006. Accessed April 18, 2012. http://www.inive.org/members_area/medias/pdf/IniveMilos200630_Synnefa_6P.pdf.
Source: International Workshop on Energy Performance and Environmental Quality of Buildings, July 2006
Publication Date: July 2006