Design optimization of energy efficient residential buildings in Tunisia

A sequential search technique is applied to optimize the design of residential buildings in Tunisia in order to minimize their life cycle energy costs while increasing their energy efficiency. In the analysis, design features of air-conditioned single-family homes (i.e., villas) are considered including orientation, window location and size, glazing type, wall and roof insulation levels, lighting fixtures, appliances, and efficiencies of heating and cooling systems. First, the results of the sequential search technique are compared against those obtained by a more time consuming brute-force optimization approach. Then, the optimal design features for villas are determined for selected locations in Tunisia. The optimization results indicate that adding roof insulation, reducing air infiltration, installation energy efficient appliances, lighting fixtures, and heating and cooling equipment are required energy efficiency measures to design high energy performance homes throughout climatic zones in Tunisia. In particular, it is found that implementing these measures can cost-effectively reduce the annual energy use by 50% compared to the current design practices of homes in Tunisia.