The security of supply in the electricity sector remained on a high level, even improving slightly in 2013, the Federal Network Agency (BNetzA) informed. System disruptions per connected end customer measured according to the System Average Interruption Duration Index (SAIDI) fell from 15.91 minutes in 2012 to 15.32 minutes in 2013, a level well below the average of 16.92 minutes for the period from 2006 to 2012.
There has been no significant adverse impact of the German energy transition (Energiewende) toward a mainly renewable energy supply and the increasingly decentralised power input on the security of supply with electricity in 2013, Jochen Homann, President of BNetzA said. He pointed out the high level of security in Germany compared with other European countries.
The decrease of the SAIDI index was due to less damage to live parts by third parties, i.e. persons, animals and vehicles like disruptions of power lines due to excavations. In contrast disruptions on the medium-voltage level caused by repercussions (Rückwirkungsstörung) increased for the third consecutive year. BNetzA considers disruptions due to the malfunctioning of upstream or downstream grids, in customer installations or power plants feeding into the grids as repercussions.
According to the German Energy Act (Section 52 EnWG) German electricity grid operators have to submit an annual report regarding the security of the energy supply, stating the time, duration, extent and cause of interruptions, which occurred in the last calendar year. For 2013 868 grid operators reported roughly 179,000 supply disruptions in 878 grids.
The SAIDI index, however, does not record all disruptions. It neither includes planned disruptions nor disruptions due to force majeure. SAIDI only records unplanned disruptions resulting from atmospheric effects, actions of third parties, repercussions from other grids and other malfunctions in the sphere of the grid operators. Besides, the disruption of the electricity supply has to last longer than three minutes.
Source: Federal Network Agency