Competition and Markets Authority
This follows the Competition and Markets Authoritys (CMA) final decision that they should be varied, which was published in April.
Rough is a gas field in the North Sea used to store gas in the summer and deliver it in winter when the gas is needed to help meet high demand. It is an important part of the UKs gas storage infrastructure and capacity.
The previous undertakings included an obligation for Centrica Storage Limited (CSL), the operator of Rough, to offer for sale a specific amount of capacity before the start of each storage year and limit the amount which can be supplied to its parent company Centrica.
In its final decision the group of independent CMA panel members carrying out the review found that as Rough ages its performance may become increasingly unpredictable, so that CSL cannot meet the previous capacity obligations.
The varied undertakings introduce an adjustment mechanism which would allow Ofgem, as energy regulator, to vary the capacity obligations - if CSL is able to demonstrate that there is an issue which will have a substantial impact on Roughs capacity.
Further details can be found on the case page.