The reduction of pollutant emissions and greenhouse gases, as well as the strong energy dependence on fossil fuels (gas and fuel oil), have, among other reasons, led many countries in recent years to develop policies to promote and encourage the use of alternative, sustainable, clean and predictable sources of energy. This paper presents an overview of the production of electricity from renewable sources (PE-RES) in Spain, and offers an outline of the current level of development of renewable energy. It also reviews the current support system, the costs of integrating renewable energy into the electric system as well as the effects of this type of energy on the electricity wholesale market price, the Gross Domestic Product (GDP), the environment, human health and employment. (C) 2013 Elsevier Ltd. All rights reserved.