Effect of Using Roof Structure as a Solar Collector for Space Heating

The conservative roof structure in Iraq was operated to collect solar radiation for housing space heating. This technique included painting the external roof surface with high absorptive paints and covering it by insulated glass 10 mm air space. An air gap of 10 cm was left between the roof surface and glass. By employed the roof as a solar collector called roof solar collector in the present work RSC and is used mainly for northern oriented spaces of the building. The suitable sun altitude angle and relatively high solar intensity in Iraq compared with European regions in winter months make RSC suitable for Iraqi residences. The test room measures 3.2 m x 3.1 m x 2.87 m in Baghdad city/Iraq (33° 19′ N, 44° 25′ E). The roof is constructed of 4 cm cement Shtyger as a roofing material, 5 cm soft sand, 5mm of felt and membrane, 10 cm h.w. concrete and 1 cm finish. Temperature measurements were done using LM 35 thermistors with data acquisitioned. The results obtained showed a reasonable increase in indoor temperature by using roof solar collector. The maximum averages indoor temperature using roof solar collector were reached the comfort level for all winter months while the minimum averages were slightly decreased below the comfort level. The monthly average energy saving using roof solar collector was reached 213kW/Hr.