Supply outages failed to curb demand for storage injections in the past week as British natural gas stocks grew once more.

The unplanned shutdown of Total's Elgin/Franklin North Sea oil and gas field curtailed pipeline deliveries to the British system, while Norwegian Langeled deliveries were also reduced at the start of the week.

But mild weather prevented any major prompt contract price rises, so capacity holders were able to exploit the spot's discount to the curve and inject gas into storage.

Total stocks rose by 296 million cubic metres (Mm³) in the week leading to 29 March, taking stocks to 2.624 billion cubic metres (Gm³) - equivalent to 55% of capacity.

Stocks are 81% higher than the level of some 1.45Gm³ at the same time last year, even though more gas - 352Mm³ - was injected in the same week of 2011.

But, unlike the injections in the week to 22 March this year, the vast majority of injections this time was made into medium-range sites rather than the long-range Rough.

Medium-range stocks increased by more than 50% to 490Mm³ from 316Mm³ a week earlier, largely because operator Centrica Storage limited Rough's 26-31 March injections to just 123Mm³, which took total long-range stocks to 2.120Gm³.

Meanwhile, stocks in short-range sites remained steady at 15Mm³.

LNG stocks

A rare rise in LNG stocks was registered during the week as British terminals enjoyed a period of increased activity.

The arrivals of the Al Samriya, Umm Slal, Al Thumama and Zarga were split between the South Hook and Isle of Grain terminals, taking stocks to 60% of capacity - equivalent to 750Mm³, the highest LNG volume in store since 7 March - by the end of the week.

Stocks could take a hit in the coming week because of the recent diversion of the Methane Nile Eagle, which was originally destined for the rarely used Dragon sub-terminal, leaving a cargo aboard the Al Ghuwairiya as the week's only expected delivery, arriving on 4 April. JT

Copyright 2012 Heren Energy Ltd. All Rights Reserved.

(Originally published March 30, 2012, in European Spot Gas Markets.)