Re-Powering Italian Wind Farms: a Feasibility Study from Theory to Practice

The installation of new renewable power plants in Italy is currently hindered by various concurrent factors, the length of the authorization process above all. The average time to authorize a wind farm is about five and a half years, mainly due to the binding judgment of the EIA (Environmental Impact Assessment). Italy however is now in a phase where many of the first-installed wind farms are close to their end of life. In this perspective, a promising solution is given by the re-powering of existing wind farms, since they can access a simplified authorization procedure under the Legislative Decree 08/11/2021, n. 199 et seq., which reduces by one third the bureaucratic burden and it lets non-binding the evaluation of the landscape authorities. Moving from this background, the study provides a feasibility study on the re-powering of Italian wind farms. Starting from the database available at GSE (Gestore dei Servizi Energetici), a new re-powering scenario has been defined, accounting for the constraints on the site area, number and dimension of the turbines imposed by the art. 32 of Law 29/07/2021, n. 108. The effectiveness of the re-powering intervention has been evaluated in terms of energetic yield, considering the increased capacity factor of the new turbines, economic revenue and environmental footprint. To verify its feasibility on a real application, a wind farm owned by AGSM-AIM S.p.A., for which wind, terrain, and production data were available, has been selected. Different plant layouts have been analyzed in the WindPro software, and compared in terms of power, producibility and capacity factor. The feasibility of the different layouts has also been verified by on-field inspections.