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EyebrowProduction extremely important to us.” it is uncertain what is possible. the gap identifed and actions drawn up

EnQuest has seen 84% production But, the frm is also adapting its orga- to close the gap. You have to be skilled to growth on the Thistle platform since it nization. “Mostly we have the tools and build MBOS application, but for the end took the facility, and a tranche of others technology to optimize production better. user it is easy to use.” including the Heather platform, in 2010, But we are not using it in the best way,” “We do now have a tool to measure if from a Lundin and Petrofac joint venture. Johnston says. “We have set up a new we are optimized,” she adds. “We believe

First, production from Thistle, which multi-disciplinary optimization group, we are optimizing production by 1-4%. is 275mi north east of Aberdeen, in 161.5 which is coming into effect right now, MBOS is also good for modeling ‘what if’ water depth, was in 1978, with a planned fully focused on measuring losses and scenarios and more and more engineers 25-year operating life. Up to the end of how to optimize them across assets. It is out-with the immediate team are coming 2013, Thistle had produced 10MMbbl. a reorganization in Nexen, moving from to us with these.”

EnQuest has since added 20MMbbl of asset-based support groups to functional

Wintershall reserves to Thistle through drilling and a support groups.” late life extension project, McCulloch said.

Nexen is also developing a step-up Wintershall, like EnQuest, took over an

The project, called LLX, saw £170 culture for staff to “own barrels,” he says. asset that had already been producing for million spent extending the facilities on “Quite often people don’t recognize they a number of years. The frm took over

Thistle, shooting new seismic, reactivating can infuence barrels can be added,” operatorship of the northern Norwegian the drilling rig and investing in the well Johnston says. Nexen is also focusing on North Sea Brage platform, its frst stock. The frm also invested in making competences and training. Control room operated producing asset, in 2013. sure electrical submersible pumps got operators have been rotated through a The frm initially focused on invest- reliable power and brought the platform’s gas lift awareness course, for example. ment, debottlenecking, and techni- st controls systems “into the 21 century.” “We also have an opportunity register. cal integrity on Brage, says Alv Bjørn

When EnQuest acquired Thistle it Investments that might debottleneck Solheim, technical director and deputy was producing about 3000bbl. Enquest operations and across asset and discipline, managing director, Wintershall. Work increased that to about 18,000 and now such as well intervention,” Johnston says. included infll drilling, but because it is at about 10,000, McCulloch says. drilling from the Brage facilities was “Ninety percent of that production is restricted to within 9300m, the frm is

BP from wells we have done something with assessing a subsea template for new pro-

EnQuest – whether it is an intervention, a work- BP also has a multidisciplinary produc- duction wells in the north of the feld.

EnQuest has invested and is continuing over or a new well or if we have added tion enhancement team, but it has gone Drilling would then be via a rig in the to invest in its assets, which it took over an ESP,” McCulloch says. a step further, creating a modeling-based feld and the one of the Brage facility, in 2010, as well as drilling new wells, EnQuest is planning to the same on its system optimization program, which it Solheim says. Wintershall shot new seis- according to McCulloch. Last year, as a Heather, from which it has just com- calls MBOS, to improve optimization. mic over the area this summer and will “In 2013 we set the challenge, are we result, EnQuest achieved 83% produc- pleted the frst couple of workovers in look to start execution phase in 2016, optimized? We needed to do something tion effciency across its North Sea about 10-11 years. with marine operations in 2018, and frst differently,” says Gillian Goby, production portfolio. In 2014, year to date, it is 90%. oil in 2019. But, the new subsea template enhancements team leader, BP. “Despite the age of our asset base project will be dependent on project eco-

Nexen (about two thirds of EnQuest’s assets are “The frst step was to enhance the tool nomics, which are marginal, he says.

Nexen has been using the Choke model, beyond their design life), we’ve main- set we had and the fnal step was to fnd Control systems on Brage also needed set out by BP in SPE paper 36848, to tained a largely fat operating cost over new ways of working,” she says. “The changing and work to “shape-up” the capture losses data and move forward to four and a half years,” McCulloch says. application itself is automated, creating a platform needed to be done. Longer term, improve effciency. The choke model looks

Since taking over the Kittiwake platform simulation every week, as a minimum, as “We want more collaboration, gluing at four main elements – reservoir, wells, in March this year, the frm has more well as when it is needed. The simula- together the onshore and offshore via plant and export systems, says Dennis than doubled production and halved tion shows teams what the optimum video conference and modern technol-

Johnston, production engineer, Nexen. operating costs per barrel, he said, with production could be on the asset, this is ogy, Solheim says.

Part of the problem, Johnston says, is that more still to come from the asset. then compared to the actual output, and “We are also looking into the main- operators do not always understand “We believe that high production eff- tenance system, all the critical their effciency rates. How operators ciency is no accident,” McCulloch says. maintenance that we have and the assess what they are doing to reduce “Part of it is capital investment. We invest frequency of the maintenance. It losses is not always clear either, and we see the results. It is also an intense was put in place in 1993, or even with no real system to close loops on focus on operational delivery and results. 1992, when the platform was built, losses identifed, other than action-

It is a relentless focus in operations and and has not been looked at since based systems, with loss entries often projects, on things such as production eff- then. “Late life is a hard life but it not reviewed diligently and different ciency and life extension. Every day off- is also exciting.” shifts having different views. shore the out-put production is a result of all the inputs. It is how the operators and Nexen has been investing in its

FURTHER READING their supply chain go about their daily surveillance and extracting more business – hourly, weekly, yearly. We all data, as well as building digital oil have to look at that. One of our philoso- felds to help process the data, to Read “Production Effciency Pain & phies is minimizing waste and controlling better understand its losses. Nexen Gain” on OEDigital.com.

our costs and also fundamentally main- is also performing more process

EnQuest’s Kittiwake platform in the North Sea. Photo from taining the integrity of our assets, that’s trials, to determine capacity where

EnQuest.

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