Buildings are a major consumer of energy and thus have a significant impact on the environment. The use of artificial lights is a major contributor to the energy usage in a typical office building using electricity to run the lights and also increasing the cooling load due to its heat dissipation. Proper design for the maximization of natural light helps reduce the use of artificial lights and results in reduction in the buildings energy consumption. Computer simulation of the lighting and energy consumption in a typical tall office building in Dubai-UAE is used to optimize the effectiveness of natural lighting penetration and calculate the associated energy savings. Two alternative building designs are proposed and tested. The overall energy savings for the whole building reached 31.4 % for the proposed oval shaped design. This represents a significant reduction in the buildings electricity load and thus its impact on the environment