Nova manifolds and spools safely installed ahead of schedule
The two manifolds for Wintershall Dea’s Nova project in Norway have been safely installed in the templates on the seabed, marking another key milestone in the delivery of the subsea development.
Subsea 7 safely installed the production and water injection manifolds as well as the pipeline spools at 370 meters water depth.
“With the installation of the manifolds and spools we have successfully begun the subsea campaign for 2020. We focused heavily, with our key suppliers, on the planning phase to ensure a safe installation. So delivering the milestone without incident and ahead of schedule, that is particularly gratifying,” said Dennis L. Dickhausen, Wintershall Dea Nova Facilities Vice President.
Installation of the manifolds and spools is a key milestone in delivery of the Wintershall Dea operated project, which will deliver hydrocarbons via two new subsea templates to the nearby Gjøa platform in the Norwegian North Sea.
Subsea 7’s vessel Seven Arctic transported the manifolds and spools from the supply base in Florø to the Nova field, 120 kilometers northwest of Bergen, before installing them below the ocean surface.
The vessel Siem Spearfish then connected the three production spools, which had been installed using a single lift, and the injector spool, to the manifolds and pipelines.
Bård Owe Bakken, Nova Subsea Manager, said: “Our main subsea contractors Aker Solutions and Subsea 7 did a great job in the planning, fabrication and installation of the Nova manifolds and spools. Despite the challenging environment, Subsea 7 managed through careful planning and efficient delivery to finalise installation even earlier than scheduled.” Installation of the water injection manifold and spool was originally planned for June.
About the manifolds and spools
The manifolds are an interface between the subsea Xmas trees, and the pipelines and umbilicals. The 212 tonne production manifold will receive the Nova hydrocarbons before sending them through the pipelines to Gjøa. The 116 tonne water injection manifold will supply water from Gjøa into dedicated wells for pressure support in the reservoir. The spools connect the manifolds to the pipelines.
Nova is located about 120 kilometers northwest of Bergen and approximately 17 kilometers southwest of the Gjøa platform in the Norwegian North Sea.
Partnership: Wintershall Dea (operator 45%), Capricorn Norge AS (a fully owned subsidiary of Sval Energi AS) (10%), ONE-Dyas Norge AS (10%), Spirit Energy Norge AS (20%) and Edison Norge AS (15%).
Water depth: 370 meters
Development solution: Nova is being developed as a subsea tieback connecting two templates to the existing Gjøa platform which is operated by Neptune Energy. Gjøa will receive the production fluids and provide water injection and gas lift to the Nova field. Oil from Nova will be transported from Gjøa through the Troll Oil Pipeline II to Mongstad, associated gas will be exported via the Far North Liquids and Associated Gas System (FLAGS) pipeline to St Fergus in the UK, supplying the European energy market.
The use of existing infrastructure enables a cost-efficient extraction of the resources in the reservoir at 2,570 meters below sea level and extends the economic lifetime of the existing infrastructure.
Nova will be Wintershall Dea’s fourth operated subsea field in production in Norway.