Norway’s Equinor (previously Statoil) and partners in the Johan Sverdrup North Sea oilfield have installed the topside on the drilling platform.
The 22,000-tonne topside for the drilling platform was lifted into position in one single lift on the Johan Sverdrup field last weekend, Equinor said in a statement, completing the second of four platforms in the first development phase of the giant Johan Sverdrup field.
The Johan Sverdrup drilling platform is now fully completed and 85 percent fully tested. The last phase - hook-up and testing – will now begin, Equinor said. The platform is due to become operational later this year, and the tie-back to the platform of eight wells pre-drilled by the Deepsea Atlantic semi-submersible in 2016 starts towards the end of the year.
“We look forward to putting the drilling platform on stream, and completing the pre-drilled wells towards the end of the year and next year, preparing for first oil in late 2019,” said Stig Åtland, head of drilling and well for Johan Sverdrup.
Then the drilling platform will start drilling new wells on the field, both for the first and second phase of the Johan Sverdrup development. Overall, as many as 48 wells may be drilled.
Ståle Hanssen, project manager for Johan Sverdrup jackets, installation and commissioning, said the technology enabling single-lift installation of big platforms as a game changer for the industry.
Up until now big topsides have been modular in design. No crane vessels have been able to lift more than 12,000 tonnes in one lift, he added. The new lifting technology on Allseas‘ Pioneering Spirit vessel, however, allows entire topsides of up to 48,000 tonnes to be lifted in one, single lift.
The technology was initially developed for the removal of scrapped platforms. Equinor is the first user of the technology for the installation of big, new topsides. This allows for great savings in the construction and installation phases, both in terms of manhours and costs, and, not least, reduces risks related to health, environment and safety, the company said.
“Equinor and the Johan Sverdrup partnership, working closely with Allseas, make a break-through for the industry here. The safety-, schedule- and cost-related benefits are substantial, and we expect that many others will follow suit,” said Hanssen.
“At the same time making the Johan Sverdrup planning puzzle so dependent on a vessel that was in fact at the time not even fully completed was no easy decision. We of course spent much time with the Johan Sverdrup partnership before coming to this conclusion,” he said.
Pioneering Spirit will return to the Johan Sverdrup field in the spring of 2019, to install the two last topside structures in the first phase of the development, for the processing platform and the utility and accommodation platform.
Overall the use of Pioneering Spirit will help cut one million man-hours offshore, Equinor said. This enabled the Johan Sverdrup partnership to deliver a Plan for development and operation (PDO) for Phase 1 of the development which included a three-to-six months earlier start-up of the field than would have been possible with the alternative topside installation solution. At the same time this helped cut the estimated costs for the PDO by almost NOK 1 billion.