A new phase opened for Statoil’s Snøhvit development in the Barents Sea on 31 May when installation of the first subsea template began.
This structure is one of six due to be placed over the coming month on the Snøhvit and Albatross fields, 140 kilometres off Hammerfest in northern Norway.
Four of these are templates, each with four well slots. In addition come a control distribution system, which allocates power, control signals and chemicals, and a pipeline end manifold.
The latter will provide the connection point between flowlines from the templates and the main pipeline to the land-based plant at Melkøya outside Hammerfest.
Aker Marine Contractors is responsible for doing the installation work in 250-300 metres of water from the new BOA Deep C multipurpose vessel.
Fabricated by ABB at the Nymo yard in south-east Norway, each of the templates will be lifted from a transport barge at the Polar Base east of Hammerfest.
It will then be lowered into the sea at the aft of the ship, and kept floating about 100 metres beneath the vessel with the aid of a pennant buoy attached to the ship.
The next stage is to tow each template individually out to the field for controlled submersion until the unit sits on the seabed.
“We’re pleased to have got these operations under way and want to achieve the best possible result,” says Siv Skadsem, project manager for subsea installations on Snøhvit.
“These are the first offshore installations in the Barents Sea, and in that respect represent a milestone.”
In addition to the subsea units, Snøhvit is being developed with a pipeline to land and a gas processing and liquefaction plant at Melkøya.
This gas and condensate field is the first development in the Norwegian sector of the Barents Sea, and the first in Europe based on gas liquefaction.