In renewables, namely wind power, the evidence of discrepancy between the installed and the used capacity needs to be studied in depth. The wind idle capacity is analysed, through panel data techniques, for a set of 18 European countries for the time span 1998-2011. Notwithstanding the so-called common policy guidelines within the countries, contemporaneous effects among countries were not proven. Socio-economic factors should be considered in order to understand the phenomenon of wind idle capacity. Policy measures that stimulate additional wind capacity are also contributing towards increasing the phenomenon of idleness. This fact should be taken into consideration by policymalcers, who must refocus their policies towards enhancing technological efficiencies. Both the substitution effect and the lobbying effect are found for conventional sources, which could be smoothing larger idle capacity inefficiencies. (c) 2013 Elsevier Ltd. All rights reserved.