The transmission tariffs consist of capacity and commodity charges that apply for use of the transmission natural gas network systems.
The tariff calculations are based on the allowable revenue, as agreed with the Commission for Regulation of Utilities (CRU), and forecast demands. Allowable revenue is calculated to reward the Gas Networks Ireland investment in each of the transmission systems and also to recover allowable operating costs. Forecast capacities/demands set at the outset of the gas year are based on expected reserved capacity and expected commodity use of gas. There is a 90:10 capacity/commodity split to recover the allowable revenue of each system.
For the purpose of the tariff, the transmission network has been split into four separate systems: three entry and one exit. There are four sets of transmission tariffs (capacity tariff and commodity tariff) as follows:
(1) Interconnector System
(2) Inch System
(3) Bellanaboy system
(4) Onshore System
A capacity and commodity tariff is payable in respect of each system which a shipper wishes to use. Shippers are obliged to pay system charges in respect of their use of the entry and exit systems.
The EU network code on harmonised transmission tariff structures for gas requires that TSOs publish certain information (in a standardised format) relating to the calculation of allowed revenues and the calculation of tariffs.
This information can be found here.
Short term capacity prices for monthly and daily capacity products at entry and exit points are set annually. These charges are a percentage of the annual tariffs.
Gas physically flows in one direction from Moffat, Scotland, into Ireland, Northern Ireland and the Isle of Man. A virtual reverse flow service between Ireland and Moffat is also available. This facilitates the virtual movement of gas from Ireland into Great Britain. From 1st October 2017 to 30th September 2018 the CRU Approved Registration Fee for Moffat VRF is €26,253.
The CRU approved Transmission Tariffs for the current year can be viewed below: