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Rationalization is a complex work, which involves several grid components at the same time and often includes the dismantling of some grid segments and the construction of new lines.
Rationalization work consists mainly in:
  • replacing plants with superior ones, such as, for example, introducing new 380-kVi links to replace a larger number of lower-voltage lines
  • eliminating parts of the grid whose usefulness is nil or negligible after the construction of new infrastructure constituting an upgrade
  • integrating new grid components, for example stations, to avoid having to upgrade saturated lines.
Especially in the vicinity of cities, rationalization constitutes a solution to problems connected with the presence of electric infrastructure in areas that are being gradually urbanized. Overall, in the rationalization work provided for by the Developmenti Plan infrastructure demolition greatly exceeds construction, with a net positive effect in terms of freeing the local communities from the presence of electric lines. The demolition of stretches of line made possible by the construction of new lines constitutes the most significant contribution in favor of the environment entailed by the development of the grid. 

Laying cables underground eliminates or reduces the negative impact on the landscape that is typical of the overhead stretches of lines. For this reason, local institutions often request underground cables as their first option for the construction of new lines. Underground cables actually have a number of technical and economic drawbacks. They are less reliable over time than overhead lines and take much longer to repair in case of malfunction. For this reason they often do not ensure adequately secure the electric system and service continuity. Furthermore, underground cables need appropriate roads when they are being installed and entail construction costs that are normally five to ten times higher than those of overhead lines.      

Reclassification includes the upgrading of existing electric lines to a higher voltage through the construction of new lines and towers to replace the existing ones. This work may entail the replacement of the old towers by a larger one that occupies more space, as happens when, for example, a 130-kVi line is upgraded to 220 kV. However, with respect to the construction of a new line, upgrading has the advantage of generally using already existing infrastructure corridors, thus avoiding the occupation of new portions of land.

Enhancement work aims – for example, by increasing the height of the supports – to reduce the exposure of the local population to magnetic fields. (Link a  “Electric and magnetic fields: the limits prescribed by the law”) Upgrading can also include changing the corridor, while at the same time dismantling stretches near clusters of population.