Pierpaolo Girardi* International Conference on High Voltage Transmission and the Visual environment Grand Hotel, Reykjavik -Iceland, 16-17 Settembre 2010 PRESENTAZIONE POWER POINT * RSE SPA The external costs methodology, applied to the energy system, has been developed in the frame of the European Project ExternE (started in 1991, www.externe.info), and further improved and refined in the frame of the recent project NEEDS (New Energy Externalities Development for Sustainability, 2004-2009; www.needs-project.org). The focus of the two projects has been on the electric power generation, with particular emphasis on the adverse effects of airborne pollutants. If great efforts have been made for the quantification of power generation externalities, the external costs of electricity transport have been somehow neglected. The problem appears to be a challenging one, because –on one side- it is highly site dependent, and –on the other side- the impacts to be evaluated often involve goods that do not have a “market” (e.g. the landscape, the biodiversity etc). Experts share the conviction that the most important impacts are concerned with : landscape, land use and territory, electromagnetic fields (EMF), noise, ecosystems (flora, fauna, especially birds) and network power losses. RSE has developed a methodology for the monetary valuation of these impact.