On Friday 28 March, the Grane process module was transferred to a barge at Kværner Egersund, the biggest operation of its kind ever to take place in Norway. Some 12,000 tonnes were moved using some 2000 wheels and 444 axles.
The Grane project has entered into its most intense phase, now that all the moduleshave been completed and tested. They are now being loaded on to barges in preparation for transport to the field and installation.
Friday's operation in Egersund was most spectacular, given that the process module is the biggest and heaviest of the Grane modules. Loading is followed by a very intensive period of 10-12 days when the module is subject to seaworthiness tests and preparations for the voyage offshore.
The first structure loaded on to the barge last week was the flare boom. One day later, the power generation module and living quarters were ready for transport at Kværner Rosenberg in Stavanger.
The approximately 6,000 tonne heavy module was turned 180 degrees prior to being loaded on board the barge. The operation commenced early in the morning, and four hours later the module was safely on board the barge and the job of securing it to the infrastructure could begin. On land, trailers were lined up ready to take the transporter carriages to Stord for the loading of the drilling module.
The drilling module at Stord was loaded on board the barge on Sunday.
To move the module approximately 200 metres from the construction site to the barge, 46 transport carriages - with a total of 1072 wheels - were used.
Each wheel can carry a 6.5 tonne load. The module's weight during loading was roughly 7,000 tonnesincluding some infrastructure and other equipment.
Transport of the module commenced at midday and by 16.00 the entire module was on board the barge. Though installation of the steel jacket on Grane can start to be installed on Saturday, the earliest time on which the first module can be installed will be some 10-11 days later.
The remaining modules will then be installed by the lifting vessel Thialf. Lifting the process module will be one of the heaviest operations ever carried out offshore.
Once the modules have been installed, some 500 workmen, mainly from Aker Kværner, can start to make all the connections. An estimated 650,000 hours preparatory work will be needed before Grane can come on stream on 15 October this year.
The total price-tag for the Grane development looks like being NOK 15.5 billion, a billion less than originally budgeted. Project execution has been excellent, and the project has been on schedule at all times.
The North Sea Grane field is located 185 kilometres west of Stavanger at a depth of 128 metres.
The reservoir covers a 30 square kilometre area, with an oil column a maximum 80 metres high, and the location of its wells is challenging because the oil is viscous and the reservoir has a long transitional zone.
A total of 27 oil-producing horizontal wells will be drilled on Grane. To ensure maximum production efficiency, the wells will be drilled exactly nine metres above the interface between oil and water in the reservoir.
Recoverable reserves amount to 705 million barrels oil. Expected production is 214,000 barrels per day. The licence holders are Hydro (38.0 percent), Petoro (30.0), ExxonMobil (25.6) and Conoco (6.4).