Private French operator Perenco has sanctioned a $150 million scheme to install slimmed-down compression equipment on a self-elevating platform to cut the running costs and extend the life of two ageing UK southern North Sea gas fields.
Dubbed SHARP — or Southern Hub Area Rationalisation Project — the project will remove redundant compression kit from each of the Leman 49/27 and Indefatigable (Inde) 49/23 fields and replace it with a single set of low-pressure compression equipment that will serve both fields.
Leman and Inde were originally developed with their own dedicated low-pressure and high-pressure compression equipment but requirements have declined as the fields have matured and flow rates have fallen.
The project has two main workscopes — a brownfield element will simplify the existing manned hubs into unmanned platforms and a greenfield element will involve the conversion of a jack-up unit into a new compression platform.
Perenco has now confirmed the project was sanctioned over the summer after the completion of front-end engineering and design work in May.
Officials said a jack-up was secured in August and a drydock campaign was due to have started by the end of September. The identity of the jack-up has not yet been revealed.
Meanwhile, tendering is ongoing for detailed engineering for the required process modules, with recommendations having been made by Perenco pending approval by its licence partners.
“These big hubs are 50 years old and in spite of our best efforts they are becoming more challenging to operate,” Laurent Combe, Perenco’s UK southern North Sea general manager told Upstream earlier this year.
“You have to spend more and more efforts trying to maintain them.”
Inde comprises three bridge-linked platforms — a production facility, a compression facility and a living quarters platform. Leman has five facilities. The complexes also comprise numerous satellite platforms.
The plan is to decommission some of the existing facilities, transform others into normally unattended installations then install the self-elevating platform housing the new compression equipment alongside the existing Leman 27 Bravo (27B) platform.
“The objective is to install equipment that is right-sized for the flowrate we now have. So, in terms of cost and maintenance and people needed to operate it, it would be a lot less than having two oversized compression hubs,” said Combe.
“We will have fewer jackets, less steel to maintain. Instead of having two offshore teams we would have just one team located on the new compression jacket we intend to have, on Leman 27B.”
At current gas prices of about 40 pence ($0.50) per therm, Combe said Leman and Inde could have faced closure in about five years’ time without the new project.
However, the fresh investment could inject “at least a further 10 years of production”.
Perenco has already carried out a similar project at its Trent field and is using that as a benchmark, he added.
It has also carried out another project to rationalise compression in the northern portion of its southern North Sea assets, comprising the Ravenspurn North and Cleeton fields, which export gas to the Dimlington terminal in Yorkshire.
That involved removing all offshore compression and using the onshore compression facilities available at Dimlington.
However, Combe said doing the same at Leman and Inde was not possible due to limits on compression capabilities at Bacton, the onshore terminal that receives output from the southern portion of Perenco’s southern North Sea assets.
Perenco confirmed earlier this year it was considering selling its UK southern North Sea assets.
According to media reports, the company decided to launch a strategic review after receiving approaches from “several oil and gas companies and infrastructure funds” last year, a company email to staff revealed.
The email reassured the workforce it will be “business as usual” during the review and that there will be no job cuts and that all Perenco’s £160 million ($205 million) of investments planned for 2019 remain unchanged.
