THERMAL EFFICIENT ISOLATING MATERIALS FROM AGRICULTURAL RESIDUES TO IMPROVE ENERGY EFFICIENCY IN BUILDINGS

Growing increase of human activities in recent years has resulted into an unprecedented increase in Energy use. With very little awareness in the utilization of Renewable Energy, in some region in Africa, the emergence of new innovative technologies with respect to energy efficient is minimal. This leads to high energy consumption cost in ensuring appropriate comfort level in building especially residential. This research looks at the possibility of using Agricultural residues in Namibia to develop appropriate materials that can be used to ensure more efficient energy consumption in residential buildings in Namibia or any semi-arid region.Vary mixed percentages of residues of maize, millet, rice and cow dung were designed to developed eleven 220cm by 110 cm by 40 cm board samples (labelled AK) from residues of maize, millet, rice and cow dung. The samples were compacted, sun dried for 7 days and tested for thermal conductivity and thermal resistivity using a thermal conductivity test machine EP500e. Results from the eleven samples tested revealed that sample C (composed of 10% maize, 10% millet, 30% rice and 40% cow dung) gives the lowest thermal conductivity (i.e. of 54.65 mW/(m*K)) and the highest thermal resistivity (i.e. 0.6935 m2K/W), hence a very good thermal efficient as compared with sample A (composed of 40% maize, 30% millet, 10% rice and 20% cow dung) that gave the highest thermal conductivity and lowest thermal resistivity, hence considered poor thermal efficient. Regression analyses conducted between the best (i.e. sample C) and the worst (i.e. sample A) revealed R 2 value of 95% and 91% respectively.