GRIP CEE 2017 / Main Report

4.3.1.1 Winter period

From each country, entry capacities at each interconnection point, as well as the withdrawal capacity of storage facilities, national production, domestic demand, and exit capacities to neighbouring countries are used for the calculation of regional N-1. After a matching/correction of entry and exit capacities of each interconnection point (lesser-of rule), the surplus gas is allocated to neighbouring countries to meet the domestic demand of countries which are “in need”. The N-1 value for winter is calculated for each country by setting the interconnection points of the main supply corridor to zero or to a minimum volume that an upstream country (next or nearer to Ukraine/Belarus transport to a relevant interconnection point) is able to export. If the investigated country has surplus gas after satisfying its demand for sharing, the gas is then allocated to downstream countries, where necessary. These values are used for the N-1 calculation as entries for a particular country. In case the N-1 value is equal to or above 1, this means that the respective country is able to cover its own demand in case of a gas supply disruption via Ukraine or Belarus. Under the assumption that underground storage facilities are filled up during the summer period (as the N-1 calculation assesses the infrastructure, not the supply standard), the maximum deliverability has been applied. The stock levels of underground storage facilities, as well as the duration of the disruption, have not been taken into consideration in the winter formula. The N-1 Formula for the winter period is based on REG 994/2010, when the technical capacity of the single largest gas infrastructure in the original formula is replaced by all interconnections with Ukraine (or Belarus respectively) in the modified formula for the CEE GRIP.

Winter N-1 Formula:

Where: EP_IN

All border entry points (transmission and LNG) capable of supplying gas to the calculated area (GWh/d)

P

National production, entry capacity (GWh/d)

S

Storage, entry capacity (withdrawal) (GWh/d)

D_MAX

Domestic winter peak demand (1 in 20) (GWh/d)

52 |

Central Eastern Europe GRIP 2017