• Electrical energy consumption in the residential sector has soared over the years. This is largely due to the growing number of residential housing units. The development of models allows us to estimate and predict the evolution and behavior of electricity consumption in this sector as well as its end-uses. The data thus obtained are extremely useful for the elaboration of energy-saving measures that can enhance energy efficiency. In June 2008 the Spanish government approved a set of guidelines in the document titled, Estrategia Española de Cambio Climático y Energía Limpia [Spanish Strategy for Climate Change and Clean Energy]. Its main objective was to replace conventional incandescent light bulbs with energy-saving light bulbs in the residential sector. This process would be carried out over a three-year period.