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Central Eastern Europe GRIP 2017 |
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Image courtesy of Plinovodi
4.3.1.2 Summer period
In addition to the data for entry capacities used for the CEE GRIP Regional N-1
analysis during the winter period, the working gas volumes and maximum injection
capacity to the underground storage facilities of each country are also used for the
analysis during the summer period. The summer formula is set to determine how
long a gas supply disruption through Ukraine and Belarus can last without endan-
gering the ability to cover demand and/or to fill the storage facilities in the respective
country. After a matching/correction of entry and exit capacities of each intercon-
nection point (lesser-of rule), the surplus gas is allocated to neighbouring countries
to meet their domestic demand. The N-1 value for the summer is calculated for each
country by setting the interconnection points of the main supply corridor to zero or
to the minimum volume that an upstream country (next or nearer to Ukraine/Bela-
rus transport to a relevant interconnection point) is able to export. If the investigat-
ed country has surplus gas for sharing after satisfying its demand, the gas is then
allocated to downstream countries, where necessary. These values are used for the
N-1 calculation as entries for each particular country.
Summer N-1 Formula:
For calculation purposes, the time period for injection into underground storage facilities
during the summer is considered to be 180 days in duration.
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)
D_AS
Domestic average summer demand (1 in 20) (GWh/d)
XP_OUT
Remaining gas to fulfil demand in neighbouring countries and for injection
into underground storage facilities in country concerned (GWh/d)
S_WGV
Working gas volume of underground storage facilities in country concerned (GWh)
S_X
Storage, exit capacity (injection) (GWh/d)