Summary form only given. The smart grids are electricity networks that can intelligently integrate the behaviour and actions of all users connected to it in order to efficiently deliver sustainable, economic and secure electricity supplies. One of the reasons why smart grid is generating so much interest right now is its ability to enable the integration of renewable energy into the electric power network, leading to a broader generation portfolio and potentially beneficial carbon implications. In this presentation, a general overview of the current power electronic technology that permits the integration of renewable energies into the smart grid will be analyzed. In particular, it will be described the "Smart City" project aims to develop a demonstrator of a smart grid in Malaga city in which customers and distribution companies work together to achieve sustainable energy consumption, by increased use of renewable energy sources, bringing generation closer to customers and making a commitment to rational and efficient consumption. A network of this type is essential in order to deploy electric vehicles.