The Gas and Electricity Markets Authority (GEMA) is proposing changes to the uniform network code (UNC), which sets out arrangements for the transportation of gas in Great Britain.

E.ON UK and British Gas Trading Limited, which later intervened in support of the utility’s appeal, challenged the GEMA’s decision to implement proposal UNC 0116V, put forward by National Grid Gas (NGG) and not proposal UNC 0116A, which E.ON UK had proposed.

E.ON’s proposal was that the national transmission system (NTS) off-take arrangements should remain as they currently stand, by removing the clause that means that the arrangements would expire on September 30, 2010.

Meanwhile, the NGG proposal, which was backed by the GEMA, concerned a number of changes designed to appease UK energy regulator Ofgem’s concerns about the disproportionate terms for gas distribution networks (GDNs) and gas shippers.

The changes in the NGG proposal included facilitating the introduction of increased levels of financial commitment for all NTS users (both new and existing) seeking to obtain access to the NTS and releasing NTS flexibility rights to GDNs and shippers primarily through annual auctions.

The Competition Commission (CC) said in a press release that, while it has decided not to implement the NGG proposal, it has not yet decided to put E.ON UK’s scheme into practice. The GEMA will now look into E.ON’s proposal before any further decision is made, the CC said.

The NGG proposal was scrapped as a result of concerns about the proposed reform of flexibility capacity and the cost benefit analysis on which the GEMA’s decision was based.