In its position paper, ENTSO-E stresses again its concern on the operational risk represented by the possible uncoordinated disconnection of a high amount of dispersed generation, mainly photovoltaics (PV), in the continental European synchronous area. Dispersed generation is mainly connected to the distribution network. The frequency deviation range on distributed networks is much narrower than what is applicable across the transmission systems of the 24 countries which form part of the region Continental Europe, and which includes the bulk of EU Member States.

This technical difference and its impact have been studied for several years by TSOs which have already published reports on this issue with solutions to be considered by European countries. If large shares of dispersed generation are taken out of distribution networks, as distribution grids are built to disconnect units very quickly in case of high or low frequency, this will create in turn imbalance on transmission networks. In view of the rapid and significant development of dispersed generation in recent years, the primary reserves of TSOs used to balance their systems will no longer suffice. As a consequence, TSOs in case of an incident will have no other option than to initiate major defence plans.

The ENTSO-E Position Paper stresses the need for all parties, especially national authorities and regulators, to support the implementation of the recommendations it has put out for many years now. These recommendations are, firstly and by July 2015, the carrying out of national retrofit programmes for already installed dispersed generation. These programmes will align the frequency disconnection of dispersed generation units with the rules applicable at transmission level. Secondly, the implementation for the new dispersed generation units of the frequency disconnection rules included in the draft European Network Code on Requirements for Generators, without waiting for its adoption by the Member States through comitology.

ENTSO-E has written to its members of the region Continental Europe inviting them to take actions at national level to mitigate risks. Italy has already started a retrofit programme. Germany has committed to do a similar operation. But many other EU countries are concerned and reducing the threat to Europe’s security of supply requires the engagement of authorities and regulators.

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