ENTSOG GRIP CEE 2014-2023 / Main Report

Image courtesy of GAZ-SYSTEM S.A.

3.8 Regional N-1 formula

The N-1 analysis was prepared for two scenarios of total supply disruption through Ukraine and Belarus. The supply corridors were defined by the route from the source to each country and flows to neighbouring countries were determined as the rest of the gas amount after satisfaction of the demand in the given country. Each particular analysis was prepared for the following winter periods: 1.10.2014–31.3.2015, 1.10.2018–31.3.2019, 1.10.2022–31.3.2023 and summer periods: 1.4.–30.9.2014, 1.4.–30.9.2018, 1.4.–30.9.2023. The formulas are presented below together with an explanation of all parameters. The analysis only takes into consideration the infrastructure capabilities, as it assesses the infrastruc- ture standard, not the supply standard.

3.8.1 Winter

From each country, entry capacities at each IP, as well as withdrawal capacity of storage facilities, national production, domestic demand and exit capacities to neighbouring countries were used for regional N-1 calculation. After a matching/cor- rection of entry and exit capacities of each IP (lesser rule), the surplus of gas is allocated to neighbouring countries to meet the domestic demand in countries which are “in need”. The N-1 value for winter is calculated for each country by setting the IPs of the main supply corridor to zero or to minimum volume that an upstream country (next or nearer to Ukraine/Belarus transport to relevant IP) is able to export. If the investigated country has a surplus of gas after satisfying its demand for sharing, the gas is then allocated to downstream countries, where necessary. These values are used for N-1 calculation as entries for a particular country. In case the value is equal to or above 1, it means that the respective country is able to cover its own demand in case a disruption via Ukraine or Belarus. Under the assumption that UGS facilities are filled up during the summer period (as N-1 calculation is assessing the infrastructure not supply standard), the maximum deliverability has been applied, the stock levels of UGS, as well as the duration of the disruption have not been taken into consideration in the winter formula.

n

E _ CB i + E _ UGS + E _ P

N 1 WINTER =

1

i = 2

X _ DOM

26 |

GRIP Central Eastern Europe 2014–2023