Accidents in some specific energy chains may also cause extensive and long-term impacts on the natural environment and ecosystems, as well as wider impacts on the security of energy supply and the national economy. However, when weighted with the expected frequency of occurrence, the risk associated with severe accidents in the energy chain is relatively low. The EU NewExt study shows that overall the degree of internalisation of damage8 ranges between 50% and 80% in OECD countries, depending on the technology considered. In non-OECD countries, the degree of internalisation of accident costs is considerably lower, lying in a range of 20% to 50% (see Table 6.2 for details).