ENTSOG First Report on Implementation Monitoring and Baseline for Effect Monitoring of the Tariff Network Code

10 15 5 20 %

ABRR in 2013 – 15 compared to 2014 – 16

0

–30 –20 –25 –10 –15 –5

TSO_01 TSO_02 TSO_03 TSO_04 TSO_05 TSO_06 TSO_07 TSO_08 TSO_09 2013 – 15 2014 – 16

14 12 10 16 18 20 %

SDBRR in 2013 – 15 compared to 2014 – 16

0 8 6 4 2

TSO_01 TSO_02 TSO_03 TSO_04 TSO_05 TSO_06 TSO_07 TSO_08 TSO_09 2013 – 15 2014 – 16

Figure 30: TAR.1 results for TSOs in Europe

Referring to all TSOs for which data is available for both periods, the average absolute imbalance over all TSOs was 6.94% over the 2013-15 period and 8.83% over the 2014–16 period   26) . Since TSO_03 appears as an outlier because of average absolute imbalances above 20%, the average absolute imbalance without this TSO was calculated and it is 4.64% and 5.84% for each period. About the average standard deviation of the balance compared to the allowed revenue (average SDBRR) over all TSOs, it was 6.08% for 2013 –15 and 6.01% over 2014–16 for all TSOs in the sample. Results show: \\ A trend towards a slight increase in the absolute imbalance (absolute ABRR) between 2013 and 2016, which means that, on average, the actual revenue of TSOs was a bit further away from their allowed revenue in 2016 compared to 2013   27) . This may suggest slightly increased instability in revenue recovery. As possible fallout, tariff adjustments may be necessary to compensate for the gap between allowed and on actual revenues. \\ A trend towards a slight reduction in the relative standard deviation of the imbalance compared to the allowed revenues (SDBRR) between 2013 and 2016, which implies that the difference between imbalances tends to be reduced over time. It means that on average the value of the imbalance gets to be increasingly stable.

 26) Intuitively, it means that a TSO was under-recovering or over-recovering an amount equivalent to 6.94% of its allowed revenue during the period 2013 –15.  27) Because of partially overlapping periods in years 2014 and 2015, the differences come from the comparison of 2013 and 2016.

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