The model does not forecast the actual flows neither can the solution proposed be considered more probable than other solutions. The actual flows will depend from decisions made by the shippers who take into account gas prices, use of system tariffs and other commercial conditions of the transportation contracts, which are not considered in the ENTSOG Network Modelling tool. We have seen in chapter 4 that prices are influenced by several parameters both technical and commercial. For this reason the utility of the model is mainly proved in the stress cases where it is crucial to determine whether there is a possibility of overcoming a supply disruption or supply minimisation, under high demand conditions, or this might be impossible, in one or more areas, because of lack of adequate transportation capacity.
In order to perform the above analysis a certain number of cases were defined by combining the values of the following parameters: \\ Demand. Regarding Demand the following options have been used: Design Case (DC). In this case the daily demand in every country is equal to the daily demand used for the design of infrastructures according to the national provisions (usually 1 occurrence in 20 years). This is the highest possible demand case. The DC demand is used in the disruption scenarios. Average day: In this case the demand in every country is equal to the average daily demand of the full year or to the average daily demand of the winter period only (AW). The AW demand is used in the study of the impact of gas source prices on flows. It should be noted that the demand is the one of the Blue Transition scenario 3) of the TYNDP 2017–26 which gives the higher values and therefore evaluate the gas in- frastructure under higher stress conditions. \\ Infrastructure level: Regarding this parameter two values were used: Low: including the existing infrastructure and the projects which have already a Final investment decision PCI: including, on top of the Low infrastructure level, the projects included in the 2015 PCI list. \\ Year: Results of years 2020 and 2030 were mainly used, however reference is sometimes made to 2017 results \\ Disruption of supply route: Two disruptions were considered: Ukraine (UA): disruption of flows through Ukraine Transmed: disruption of flows of Algerian pipeline gas to Italy.
3) Please see “ENTSOGTYNDP 2017 – 2026, Annex F – Methodology” for a more detailed description of the TYNDP 2017– 26 scenarios