OSLO, Norway—Work on the next generation of all-electric subsea production systems is being advanced, albeit not swiftly, as there is a three-way competition amongst big hardware companies.

Aker Solutions and TechnipFMC are working on developments, following in the footsteps of work done more than a decade ago by OneSubsea-cum-Cameron.

The subsea technology arena is well familiar with the false dawn of technology take-up. One can go back to the beginning of the 21st century and the development of the Troll Pilot subsea separation system by Norsk Hydro with the support of ABB. It took more than another half decade before Statoil released its Tordis seabed separation system in Norway and another similar period for Total to put down another such system at Pazflor in Angola.

So it has been with all-electric subsea production systems.

Originally developed with support from BP, Cameron—now OneSubsea, a Schlumberger company—delivered the first two all-electric christmas trees to Total for installation on the Dutch K5F Field in 2008. Technically they were not all electric, as the development of an electric downhole safety valve (e-dhsv) was slow to follow. It was not until the third tree for K5F was installed last year—which included Halliburton’s DepthStar e-dhsv— that it could described as truly all-electric.

Progress has been made.

FMC, prior to the takeover merger with Technip earlier this year, had delivered more than 200 electrically actuated valves and 38 electric subsea control modules, according to TechnipFMC’s Olav Monsson, who spoke during the Subsea Valley Conference in Oslo, Norway. The first group—16 in all—of e-actuators were supplied to Statoil for choke valves. However, either the hydraulics were problematic or the retrofit valves could not be accommodated within the existing subsea control system. The big breakthrough, though, was the delivery of nearly 80 subsea valves with electric actuators for the Åsgard subsea compression station, Monsson said.

The early electric actuators were installed with batteries, originally NiCad (nickel cadmium) and later Li-Ion (lithium ion). By the time the Åsgard project came along with a big electric power supply for all the turning machinery, batteries were not required.

Monsson said TechnipFMC continues to work on new variations of actuators for what it has done before, such as for choke valves, and possibly for high-integrity pipeline protection system applications, but taking the step up into an all-electric tree with higher safety requirements will take some time. Monsson said he expected such christmas trees to become available in 2020 or 2021.

Meanwhile, Aker Solutions has released an all-electric development project with the support of an impressive group of backers that include Statoil and Total plus Petronas and Lundin, Aker Solutions’ Einer Winther-Larsson told SEN.

The interest of the new players is specific. Petronas needs to find a way to add flexibility to existing subsea systems to add more wells, while Lundin is looking to deploy a seabed production system in the Barents Sea for its Alta Gohta prospect with a lower environmental footprint.

Winther-Larsson said at a preconference meeting that Aker Solutions’ aim is to offer a smaller, lighter christmas tree as well as reduce the size of the umbilical and the amount of topside support equipment required. The company is calling its electric actuator ELDRIVE.

TechnipFMC’s Monsson was even more specific on the emphasis of all-electric. He made general reference to projects where the umbilical was “half the cost of the entire subsea production system.”

—Steve Sasanow

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