Wind repowering: Unveiling a hidden asset

Given the abundant availability of resources, the market potential, and their cost competitiveness, onshore wind farms and photovoltaic units are expected to drive the overall growth of renewable energy sources in the next decade. However, Europe is a small and densely populated continent, which results in many countries experiencing a severe shortage of suitable land sites for installing new wind and photovoltaic facilities. This, combined with the fact that many existing wind turbines and photovoltaic units reach the end of their operational lifetime, has laid the groundwork for ‘repowering’. Repowering includes upgrading or retrofitting renewable energy sources' components and exploits existing land sites, in which renewables are operating for years. This paper intends to emphasise the multiple dimensions of repowering, also delving in its surrounding socio-economic context in various European countries, to identify its barriers and allies as well as gather best practices and lessons learnt from its implementation. Considering data availability, extent of spatial use and bulk equipment, and consequent attention in literature and practice, the analysis mainly orbits around repowering of wind projects, rather than solar photovoltaics. Finally, the paper presents key directions toward wider future exploitation of repowering.