Maersk Oil has been busy handing out the spoils for its recently approved Culzean (SEN, 32/11) development in the U.K. North Sea, although the award of the floating, storage offloading (FSO) unit for the project is still up for grabs.

Sevan Marine has said it is “optimistic” that its technology will be selected for FSO unit for the scheme in Block 22/25 of the Central North Sea, which would mean Teekay Offshore is in pole position for the award, with its concept employing a cylindrical FSO.

Teekay is going head-to-head with Modec for the FSO, which will be used to store condensate from the field.

Down below, Subsea 7 has scooped the $150 million subsea, umbilical, riser and flowline contract for the HP/HT gas condensate development.

Its contract scope includes project management, engineering, procurement, construction (EPC) and installation of a 22-in. diameter, 52-km gas export pipeline connected to the Central Area Transmission System and a 3.6-km pipe-in-pipe (10-in. outer pipe and 6-in. inner pipe) providing insulation for the transportation of the condensate to the infield FSO.

The pipe-in-pipe will be laid with a 4-in. piggy-back line that will transport fuel gas to the FSO.

Subsea 7 also will provide subsea structures, tie-ins to the Culzean platform facilities and precommissioning expertise.

Project management and engineering work will be done from Subsea 7’s Aberdeen office. Offshore activities will utilise a number of Subsea 7 vessels including the highly versatile pipelay and heavy-lift vessel Seven Borealis. Offshore operations are scheduled to kick off in 2017.

The bulk of the platform construction work, meanwhile, has gone to Singapore’s Sembcorp Marine, which has landed an EPC contract worth more than $1 billion (including long lead items) for Culzean.

The contract includes the building of the central processing facility plus two connecting bridges, a wellhead platform and a utilities and living quarters platform topsides.

The facility will be installed at a water depth of 90 m in the U.K. sector of the Central North Sea.

SMOE will provide EPC and onshore precommissioning services while detailed engineering work will be performed by a subcontracting partner.

The Sembcorp Marine Admiralty Yard in Singapore will be the core fabrication yard for the project, while, in some good news for the U.K. supply chain, the Sembmarine SLP yard in Lowestoft will undertake the work scope for a power generation module, two bridges and a flare.

Heerema has won the EPC contract for both the 8,000 mt central processing facility platform and the 6,800mt utility & living quarter platform. Construction is due to start at Heerema Vlissingen in January 2016 to be ready for sail away in June 2017.

As part of the contract, six pile sleeve clusters will be fabricated at Heerema’s Hartlepool facility in the UK, in addition to the wellhead access deck already underway at the yard.

With initial reservoir pressure up to 13,575 psi and temperature up to 175 C, the Culzean project counts as an ultra-HP/HT field and has qualified for the HP/HT Cluster Area Allowance introduced by the U.K. government as part of the 2015 budget.

In a first phase of drilling lasting five years, six producers will be installed, of which three will be online at startup. In a second phase, three replacement wells will be drilled in 2021 to 2023, reflecting the experience that producers have a relatively limited lifetime in such extreme reservoir conditions. There will be 14 well slots, so there will be ample opportunity to drill more wells if need be.

The Culzean gas field is expected to be capable of providing about 5% of the U.K.’s total gas consumption by 2020 to 2021.

Discovered in 2008 by Maersk Oil and its co-venturers, the gas condensate field has resources estimated at 250 MMboe to 300 MMboe.

Production is expected to start in 2019 and continue for at least 13 years, with plateau production of 60 Mboe/d to 90 Mboe/d.

Offshore