The simplest platform on the NCS

A brand-new concept is now under construction in the Netherlands. Oseberg Vestflanken 2 will be developed as an unmanned wellhead platform – probably the simplest platform on the Norwegian continental shelf (NCS). 

Magne Bjørkhaug is the architect behind the new concept, a concept that got its plan for development and operations approved, without comments, by the Norwegian Ministry of Petroleum and Energy, the Norwegian Petroleum Directorate, and the Norwegian Petroleum Safety Authority.

Bjørkhaug is a man who gets energy when people say: “This has never been done before.” His answer is: "I know, that’s exactly the point." 

Magne Bjørkhaug
Process Technology Advisor

Since the new installation Oseberg H will be unmanned, there will be no living quarters, helicopter deck, life boats – or even toilets on board.

He works in Statoil’s unit for research and technology, a unit whose task it is to come up with new ideas and concepts that have never before been tested, and find out how to get them working.

“A normally unmanned platform is like a cabin at Geilo. You don’t go there often, but you have all you need there, and then some. An unmanned wellhead platform will be like a cabin you very seldom visit, and when you go you bring everything you need,” Bjørkhaug explains. 

Since the new installation Oseberg H will be unmanned, there will be no living quarters, helicopter deck, life boats – or even toilets on board.

During the drilling of wells all facilities will be available on the rig, and when the platform is on stream, there will be only one or two maintenance visits a year. A purpose-built vessel will then be bridge-linked to the platform, and all facilities will be available on the vessel. The same type of vessel will be used at the Dudgeon wind farm in the UK.  

Giving life to old giants

The story starts in 2012. The price of oil was still high, but the need for simpler development projects in the future was seen by many: A concept where they started at zero, and added the necessary elements. 

The motto was: “Start with nothing and argue from there”. Later, another motto came into effect: “Think big, build small”.   

“Everyone knows that we can make big sophisticated projects, but we have really never tried to build anything simple before. This was a somewhat new approach,” Bjørkhaug says, smiling.

A fast glance at our portfolio explains why we needed a new and simple concept. In the 1980s and 1990s a number of larger fields with extensive infrastructure were developed. 

The next development projects, with few exceptions, are smaller discoveries that can be tied in to these existing giants. They can thus exploit existing infrastructure and be realised, while the supporting platforms are being fed with new production. Their productive life will thus be extended, and they will produce more of their own reserves. This increases the rate of recovery, and secures jobs. 

Concept seeks user

Subsea developments have been – and are still – a common concept, but with the price of subsea equipment tripling we need additional solutions. An unmanned wellhead platform is an excellent solution for development projects with 5-12 wells and – at least so far – an ocean depth of down to approximately 150 metres. This is the maximum ocean depth for existing jack-up rigs, the rigs that drill fields like this one.

The goal was to solve the tasks in a new and simpler way, without compromising safety.

“We never compromise safety. Ever!," Bjørkhaug underlines.

They turned over a new leaf. Initially they didn’t even have a reservoir to base this on. They had a concept consisting of a new, proprietary processing system, and were looking for its first user.  

“Then Oseberg Vestflanken 2 turned up – and it was a perfect match! We nearly burst with joy when the licence decided in favour of the concept,” Bjørkhaug says.

Prior to the investment decision the break-even for the project was reduced by a full 52 percent. But now the project could be adapted to the reservoir in order to maximise production. Four suppliers performed separate feed studies, with Dutch company Heerema coming out on top.  

Magne Bjørkhaug explains the unmanned wellhead platform concept while visiting the Heerema construction site in Zwijndrecht, Netherlands.

Could be the first of many

October 2016: Commuting weekly to the Netherlands Magne Bjørkhaug approaches us from the hut-like project office of Oseberg Vestflanken 2 at the Heerema yard in Zwijndrecht. 

“Let’s check on their progress.”

As we cross the road over to the giant fabrication halls streams of pleasant sound flow towards us. At least pleasant for those that love to see steel being made into structures, the transformation from a drawing to a facility—a feat of engineering in practice. The high squeak from welding and cutting, and the ding dong sound warning that a lift is in progress. A mixture of sounds indicates that something is being created here from drawings and thousands of steel sheets.

The Oseberg H topside will weigh 1000 tonnes. By comparison, the Valemon platform’s topside weighed 10,000 tonnes. 

“The cellar deck is being built here,” says Bjørkhaug.  We are looking down from a balcony in the hall at something that will eventually become a unique structure on the Norwegian continental shelf, the first unmanned wellhead platform, Oseberg H. Sparks can be seen from one of the well slots in the cellar deck, whereas blue welding light can be seen from another slot. 

The platform topsides now under construction will weigh some 1000 tonnes. A rather crafty, small platform. By way of comparison the topside of the Valemon platform, designed to be normally unmanned, weighed some 10,000 tonnes. 

But someone has to take the lead. Bjørkhaug praises both the Statoil management and the partners that have been willing to, and advocated, the use of a new concept, admitting that the oil price has been beneficial:

“Honestly, if we had presented this project 4-5 years ago, they’d have laughed at us. Now everyone thinks this is exciting, and I think this will be the first of several such projects.”