A major focus of existing literature on energy conservation is the modelling and quantification of energy savings and the corresponding carbon dioxide emissions from lightings. While many studies have established theoretical frameworks concerning these issues, very little documentation exists relating to energy savings and emission levels in students' hostels. This paper considers the lighting efficiency improvement of four University of Lagos halls of residence for the purpose of quantifying energy saving and the minimization of carbon dioxide that can be made. Compact fluorescent lamps are considered alternatives to the current primary usage of conventional fluorescent and incandescent bulbs. The existing electricity consumption data obtained from energy audit are used in combination with conversion factors to estimate the annual CO2 contributed to the atmosphere by lighting in each of the buildings. The result of the study shows that over 45% reduction in carbon dioxide emission can be achieved. There is a lot individuals can do to reduce the emissions, for example, using energy saving appliances, turning off appliances when not in use, less use of fossil fuels, are simple measures that can be adopted to reduce annual carbon footprint, improve economic growth, enhance environment, health and save the planet. (c) 2013 Elsevier B.V. All rights reserved.