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Ten-Year Network Development Plan 2017 Main Report
0
35,000
30,000
25,000
20,000
15,000
10,000
5,000
GWh/d
Jan 09 July 09 Jan 10 July 10 Jan 11 July 11 Jan 12 July 12
July 14 Jan 15 July 15 Jan 16
Jan 13
Jan 14
July 13
Winter
Summer
October
Figure 2.8:
Yearly modulation
2.2.2 SEASONAL AND PEAK CONSUMPTIONS
2.2.2.1 Seasonal
The gas transmission network experiences different seasonal demand levels driven
largely by the climate and heating requirements, the variation seen is represented in
figure 2.8.
Although October is seen as a winter month in the gas year, it is typically a storage
injection month. In order to capture the seasonality of the gas market in the over-the-
whole-year simulation, average demand levels for summer and winter days are
based on the storage injection and withdrawal periods, more details on this method-
ology can be found in Annex C4.
2.2.2.2 Peak day and highest 14-day period by year
The day of highest consumption in the year is a key input of the network design
process and represents one of the most stressful situations to be covered by the gas
transmission system. The design and operation of a system is also challenged by the
availability of supply sources during periods of high consumption.
On this basis, ENTSOG has considered both the peak day and the highest 14-day
demand period as significant for testing the resilience needs of the system
1)
.
However as table 2.1 shows from the last seven winters at EU aggregated level, the
highest daily consumption can often occur outside of the highest 14-days average
consumption
1) Please note that for the TYNDP assessment this corresponds to the National TSO Design Case and highest 14-day
demand relates to a 1-in-20 year situation