Genetic algorithms for ceiling form optimization in response to daylight levels

Utilization of daylight in indoor spaces creates opportunities for energy savings and is linked to increasing productivity in the workplace. This sensitive aspect in environmentally aware architectural design depends on many interfacing factors. In this research, ceiling geometry is investigated as an element that can provide control to natural light, achieved through reflection and diffusion of the external and internal reflected components of daylight. This paper presents a generic optimization procedure for architects that aids in generation and finding of curvilinear and mesh ceiling forms. The objective was to maximize daylight uniformity ratios. A genetic algorithm was developed and coded in LUA, a versatile scripting language. Radiance simulation software was employed as the backend daylighting performance calculation engine, and Ecotect as the front end form input and visualization tool. Conclusions about the optimum ceiling geometry and form for a designed example case were drawn. The presented method provided architects with a variety of choices for designs which are weighed through daylighting performance. Results showed that this approach offers a robust and yet precise form finding method.