ENTSOG Tariff NC - Implementation Document 2nd Edition

Entry points are in rows, exit points are in columns. \\ Distance between two points may theoretically vary depending on the flow scenario in case 2 points are connected via at least one unidirectional pipeline  1) . For example, in the current configuration the shortest path for gas between storage point ‘A’ and bidirectional IP ‘K’ is simply along bidirectional pipeline AK, and distance between A and K is therefore 10km. However, in a modified configuration where pipeline AK would only allow flows from A to K (not any- more between K and A), it would be still possible to flow gas at entry point K to inject gas in storage A but along the pipeline via consumption point O. Further to feedback received from stakeholders, ENTSOG would like to underline that the shortest distance to flow gas between K and A would be the sum of distanc- es KO and OA, and that this distance would be necessarily the one to use for CWD distance calculation as per Article 8(1)(c), even if alternative longer routes also exist to allow a flow scenario between K and A (e. g. KO, then OT, then TA). Distance for flow scenario AK would still be 10 km, but distance for flow scenar- io KA would be the sum of distances for KO and OA, that is 15.3km, compared to 10km in the bidirectional case. M 23/3 G 23/3 G

M

S

S

√32

√32

N

O

N

O

T

T

√13

√13

√80

√80

√137

√137

A

A

10

10

J

J

K

K

Original case: distance for flow scenario is the same for AK and KA

Variant: distance for flow scenario is now longer for KA because pipeline AK is now unidirectional

Figure 63: Impact of flow scenarios on calculated distances

\\ If an entry point and an exit point are not connected according to a flow scenario , the distance between them in both directions is indicated by a ‘ 0 ’ written in red in the previous table. For example, storage point A and storage point C are not connected according to a flow scenario: it is impossible to flow gas within the network of the TSO from A to C or from C to A because of unidirectional pipelines (section H to C is the problem in the ‘A to C’ direction, section C to E is the problem in the ‘C to A’ direction). \\ Flows from/to the same point are not considered as valid flow scenarios, and are also marked with a ‘ 0 ’ in red (e. g. impossible to flow gas from A to A). \\ Points S and T do not appear in the table since they are not relevant in tariff derivation for the CWD counterfactual (neither entry, nor exit points).

 1) Note that in Article 8 of TAR NC, the calculation of the average distance for an entry point AD En

and the calculation for

an exit point ADE X distinction between D A,B

both refer to the same distance D En,Ex

. For flow scenario reasons, Article 8 should actually make a

and D B,A .

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