In this paper, published in Ecological Economics, Filippo Beltrami (Department of Economics, University of Verona), Fulvio Fontini (Department of Economics and Management, University of Padova) and Luigi Grossi (Department of Statistical Sciences, University of Padova) investigate the role of Renewable Energy Sources (RES) on the Italian power exchange. The purpose of their analysis is to assess the impact of electricity generation from RES on the reduction of CO2 emissions and on the value of the power supply.