An evaluation of public aids towards renewable energy sources in Spain

Public aids towards renewable energy sources in Spain have had the consequence of a great increase in their use. This is particularly true for the case of wind generation. For the year 2007, we show that the savings in social costs due to carbon emissions account for a figure between 25% and 78% of total aids. Since some of the public aids are just a money transfer with no effect on total social welfare the justification of the net costs of the aids is higher. For the particular case of wind generation, we find that in the worst case scenario 45% of the social cost implied by the public aids is justified by the reduction in carbon emissions, and that the benefits of CO2 reductions are 135% higher than the costs in the best case scenario