Capacity methodology statements

National Transmission System (NTS) capacity provides the daily right to flow gas into and offtake gas from the NTS. Here, you will find NTS capacity methodology statements required under the Gas Transporter Licence, as well as associated consultations, documents, planned industry workshops and additional supporting details.

Entry capacity release (ECR) 

The entry capacity release (ECR) methodology statement describes the methodology that we use to determine the amount of entry capacity that we will release to meet our obligations in the Licence and Uniform Network Code.

The methodology statement applies to all entry capacity (i.e. existing system entry capacity and additional 'incremental' entry capacity). In particular, the statement defines the circumstances under which we will accept applications for incremental entry capacity from shippers, and thereby the level of financial commitment required from those shippers.

Exit capacity release (ExCR)

The exit capacity release methodology statement (ExCR) describes the methodology we use to determine the amount of exit capacity we will release to meet our obligations in the Licence and Uniform Network Code.

The methodology statement applies to all exit capacity (i.e. existing exit capacity and additional 'incremental' exit capacity). In particular, the statement details the commitment that shippers and DN users make when applying for, and being allocated, longer term exit capacity.

Entry capacity substitution (ECS)

The entry capacity substitution (ECS) methodology statement describes the methodology we use to determine proposals for the indefinite substitution of NTS entry capacity from one NTS Aggregate System Entry Point (ASEP), where it is not required, to another ASEP where demand for entry capacity exceeds existing quantities. In particular, it describes under what circumstances we will consider such substitutions and how we will determine our proposals to substitute capacity.

2014 annual review archive

Exit capacity substitution and revision (ExCS) 

The exit capacity substitution and revision (ExCS) methodology statement describes the methodology we use to determine proposals for (1) the substitution of NTS exit baseline capacity from one NTS exit point (where it is not required) to another in response to a request for additional capacity and/or (2) the revision to NTS baseline exit capacities at NTS Exit Points where new pipeline infrastructure installed to facilitate the release of incremental entry capacity has a beneficial impact on the availability of exit capacity. In particular, it defines:

  • under what circumstances we will consider such substitutions and revisions; and

  • the process we will undertake to determine our proposals to substitute capacity and/or revise baselines.

2014 annual review archive

Entry capacity transfer and trade (ECTT) methodology statement

The entry capacity transfer and trade (ECTT) methodology statement describes the methodology we use for the transfer of unsold, or the trade of sold, NTS firm entry capacity, for the month ahead, from one ASEP to another ASEP.

It also allows the surrender of unwanted, available capacity to be bought and allocated at the same ASEP. In particular, it defines under what circumstances we will consider such transfers or trades and the process we use to determine the quantities that we will allow to be transferred and/or traded.

Generic revenue driver methodology (GRDM) statement

The generic revenue driver methodology (GRDM) statement describes how we determine revenue drivers. These are the means of increasing our allowed revenue from the release of incremental capacity to fund the construction of additional assets and/or contractual arrangements to facilitate the release of that capacity.

The statement has been produced to comply with the licence obligation to produce a generic entry and exit revenue driver methodology to determine any additional revenue allowances relating to the release of funded incremental obligated entry capacity and funded incremental obligated exit capacity in the RIIO-T1 regulatory period.

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National Transmission System Connections

Connecting to, diverting, and shipping using the National Transmission System (NTS).

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Land and assets

Find out more about our assets, working near them, and projects we're undertaking to improve them. 

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Charging methodologies and transportation charges

The NTS transportation and connection charging methodologies are part of UNC TPD Section Y. Changes to the methodologies must be carried out using the UNC governance and change management processes.  You can find out more on the Joint Office website.  

On behalf of gas transporters, the Joint Office also publishes details of transportation charges. We publish indicative and actual charges here on the Transmission system charges page.

Go to the Joint Office website