%0 Journal Article %K Cool roof %K Heat Island %A Hashem Akbari %B Energy %D 2003 %G eng %N 9 %P 953-967 %R 10.1016/S0360-5442(03)00032-X %T Measured energy savings from the application of reflective roofs in two small non-residential buildings %V 28 %8 07/2003 %X

Energy use and environmental parameters were monitored in two small (14.9 m2) non-residential buildings during the summer of 2000. The buildings were initially monitored for about 1 1/2 months to establish a base condition. The roofs of the buildings were then painted with a white coating and the monitoring was continued. The original solar reflectivities of the roofs were about 26%; after the application of roof coatings the reflectivities increased to about 72%. The monitored electricity savings were about 0.5 kWh per day (33 Wh/m2 per day). The estimated annual savings are about 125 kWh per year (8.4 kWh/m2); at a cost of $0.1/kWh, savings are about $0.86/m2 per year. Obviously, it costs significantly more than this amount to coat the roofs with reflective coating, particularly because of the remote locations of these buildings. However, since the pre-fabricated roofs are already painted green at the factory, painting them a white (reflective) color would bring no additional cost. Hence, a reflective roof saves energy at no incremental cost.