%0 Journal Article %A Cabal, Helena %A Lechón, Yolanda %A Caldés, Natalia %A de la Rúa, Cristina %A García-Gusano, Diego %A Lípez-Bernabé, Elena %A López-Dóriga, Inés %A Santamaría, Marta %T Ex post and prospective analyses of renewable policies in Spain %D 2015 %@ 2195-1284 %U https://hdl.handle.net/11556/4779 %X In this work, socioeconomic and environmental impacts associated to energy technologies in the current and future Spanish Energy System have been estimated. This information has provided the base from which to conduct two kinds of analyses. First, an Ex post analysis of renewable policies in Spain, where the net impact on social welfare associated to the progressive introduction of those energies in the energy system has been assessed using a partial cost-benefit analysis. Then, a prospective analysis of the Spanish energy system where the optimum energy mix, which leads to the largest social welfare under different energy scenarios, taking into account a medium-long term time horizon (2035), has been estimated using the national energy optimization model TIMES-Spain. The results of the Ex post analysis of the period 2005–2012 show an increase on social welfare due to the introduction of renewable energies. Nevertheless, when assessing the total expenditure of renewables support policies, the results show this support exceeds the economic value of the socioeconomic and environmental externalities calculated in this work. The prospective analysis results for the period 2010–2035 definitely recommend a support for renewable electricity generation technologies and the redesigning of renewables support policies to better reflect their external benefits with respect to the fossil alternatives. %~