Adverse weather conditions have disrupted TotalEnergies EP Danmark’s operations, delaying production from the remaining fields at its natural gas redevelopment project in the Danish sector of the North Sea.
As a result, the company has updated its timeline for achieving full production capacity at the Tyra gas field, Denmark’s largest natural gas field.
The Tyra redevelopment project has been underway since March 2024, with the first gas export from Tyra II marking the successful initial production following a major revamp. However, challenges have emerged in the process of reactivating and optimising offshore wells, particularly in relation to the reactivation of the Tyra satellite wells. These wells are critical to achieving the anticipated production plateau, and the necessary well interventions have been delayed by adverse offshore weather.
A key operational challenge arose from issues related to two transformers supplying power to essential gas compressors, which have impeded the full commissioning of the project. Despite these setbacks, TotalEnergies has made significant progress in repairing and commissioning equipment, although the anticipated timeline for full technical capacity was initially set for mid-November 2024. Uncertainties about remaining operational conditions have led to delays.
The ramp-up phase, which is closely tied to well intervention activities, has allowed for gas production to be restored from three of the six fields. However, due to weather conditions and other operational issues, the reactivation of the Tyra satellite wells has faced further delays. Offshore weather constraints, including limited weather windows, have hindered the progress of well interventions and postponed the critical reactivation of these satellite wells.
Given the current weather forecasts, the timeline for reactivating all satellite wells to achieve plateau production has been extended by approximately three weeks. The revised timeline now places the expected achievement of plateau production in the second half of January 2025.
The Tyra field is part of the Danish Underground Consortium, with TotalEnergies EP Danmark (43.2%), BlueNord (36.8%), and Nordsøfonden (20%) as the key stakeholders.
Euan Shirlaw, CEO of BlueNord, commented, “Although it is disappointing that plateau production is now expected in the new year, we are confident that the recent above-ground challenges are well understood. Once the remaining satellite wells have been reactivated, the performance of the field will no longer be constrained by weather, as has been the case during the startup phase. We look forward to reaching plateau production in January 2025 and sharing the promising results of our HEMJ program.”
TotalEnergies points out that oil and gas supply nearly 50% of Denmark’s energy needs, and once the Tyra field reaches plateau production, it is expected to contribute around 6% of the European Union's natural gas output, marking Denmark’s return as a net gas exporter.
Additionally, in June 2024, drilling operations in the Harald East area, conducted with the Shelf Drilling Winner jack-up rig, led to the discovery of additional gas condensate resources in the Harald field, which is located in shallow waters 250 km off Denmark's west coast. These new reserves could further boost production from the region, with ongoing well intervention efforts to optimise the production from the field.
In a move expected to create the UK North Sea’s biggest independent producer, Equinor UK and Shell UK have agreed to combine their UK offshore oil and gas assets and expertise into one company.
With a 50/50 split stake between Equinor and Shell, the new joint venture will reportedly be more agile, focused, cost-competitive and strategically well positioned to maximise the value of the combined portfolio. According to Shell, the decision was made in light of the maturing nature of the basin, with production rates naturally declining. As a result, the new company will target the continued economic recovery of the resource and will invest to provide long-term sustainable future for individual oil and gas fields and platforms.
“Domestically produced oil and gas is expected to have a significant role to play in the future of the UK’s energy system,” remarked Shell plc’s Integrated Gas and Upstream Director, Zoë Yujnovich. “To achieve this in an already mature basin, we are combining forces with Equinor, a partner of many years. The new venture will help play a critical role in a balanced energy transition providing the heat for millions of UK homes, the power for industry and the secure supply of fuels people rely on.”
Equinor’s Executive Vice President for Exploration and Production International, Philippe Mathieu, added, “Equinor has been a reliable energy partner to the UK for over 40 years, providing oil and gas, developing the offshore wind industry, and advancing decarbonisation. This transaction strengthens Equinor’s near-term cash flow, and by combining Equinor’s and Shell’s long-standing expertise and competitive assets, this new entity will play a crucial role in securing the UK’s energy supply.”
In the UK, Shell currently produces around 100,000 barrels of oil equivalent per day with Equinor contributing an additional 38,000. With the new joint venture already expressing its desire to maintain rates, this could be a potentially game-changing development for the various well intervention service and equipment suppliers to the region.
The Enersea group has announced the launch of its third sister company called Frequensea
This new wing has developed an innovative decommisioning tool designed to extract power cables, that are no longer in use, from the ocean. These subsea cables are often buried as deep as three meters below the seabed, presenting significant technical difficulties.
The latest addition to the corporate family was announced at the Offshore Energy Exhibition & Conference, where Dieter Korndorffer, Managing Consulatnt at Enersea demonstrated the patented technology of Frequensea, which utilises a vibration-based mechanism that liquefies surrounding soil, enabling the efficient removal subsea power cables. This process not only facilitates the recovery of valuable metals from the cables but also supports the transition to a circular economy by recycling materials that would otherwise remain unused.
Akastor ASA, which owns a 50% share of AKOFS Offshore, has announced that Equinor Energy AS has extended its existing contract for the vessel AKOFS Seafarer.
The three-year option period has been activated by Equinor and is expected to commence in late Q4 2025. This is after the vessel has completed its customary special periodic survey and is in direction continuation of the current contract period.
According to Akastor, the option has a total value of US$300mn and will mean that the vessel will continue to perform light well intervention services for Equinor well into 2028.
Akastor’s move to acquire a 50% interest in AKOFS Offshore was undertaken in light of the “compelling” subsea well intervention and installation sector. Learn more about this development by clicking here.
Decom Engineering, a provider of green decommissioning solutions, has proved the capabilities of its ‘neutrally-buoyant’ Chopsaw on a North Sea decommissioning project.
Offshore contractor Allseas tasked Decom Engineering with designing a chopsaw specifically for the unique challenges posed by the conductor removal scope for the Brent Charlie platform decommissioning campaign. This required 40 well conductors to be cut at various water depths and needed the Chopsaw to be positioned and powered from a ROW subsea (with several cuts below the conductor guide-frame).
The tool, therefore, had to be neutrally buoyant in seawater, as well as being easily manoeuvrable with a single ROV. The Chopsaw width was also restricted to three metres due to the complexity of the conductor layout at the seabed.
"We successfully designed, manufactured, assembled, and tested the new Chopsaw within just six months, ready for offshore deployment from Allseas' heavy lift vessel Pioneering Spirit,” remarked Decom Engineering Managing Director, Sean Conway.
"The C1-32 Chopsaw has demonstrated its effectiveness in the field, completing numerous conductor cuts with an average cut time of approximately one hour. The tool's capability to perform multiple subsea cuts before needing to return to deck has saved both operational and vessel time.
"With the buoyancy functioning as designed and tested, the ROV was able to easily navigate the Chopsaw to and from each conductor, even at depths as shallow as 20 meters below sea level."
The C1-32 Chopsaw was engineered to cut conductors up to 32" outer diameter (OD), with a blade diameter of 2,100mm. Each of the 40 Brent Charlie conductors had an OD of 30 inches, consisting of both welded and Talon conductors, as well as some flexible risers.
With its neutrally buoyant design, the Chopsaw weighed approximately 6,700 kg in air but only about 50 kg in seawater, making it easily manoeuvrable by a ROV and allowing the tool to be flown into position and manoeuvred between conductors with precision.
To facilitate safe deployment and recovery, the Chopsaw was used in conjunction with a ‘deployment frame’ which allowed the tool to be quickly deployed to the correct subsea depth and safely through the splash zone. Once at the desired depth, the ROV connected the hot stabs, opened the clamps, and removed the tool from the frame.
“We have a strong relationship with Allseas, having worked for them on a previous North Sea platform removal project,” Conway concluded. “Completion of the Brent Charlie workscope further cements our credentials as a major provider of complex subsea conductor cutting services.
"Ongoing investment in R&D has been a critical factor in securing these projects and we will continue to invest and innovate so that our technologies remain as the market leader in cutting solutions."
THREE60 Energy, a leading independent energy service company, has received a multi-million-pound contract to deliver and support end-to-end decommissioning for multiple assets in the North Sea.
The contract was awarded by a major North Sea operator and covers both installation and pipeline operator scopes and initially includes three offshore assets with the option to include a further three over the six year period.
With its fully integrated services, THREE60 will deliver and support from the initial planning and regulatory compliance to project management, post cessation of production (CoP) operations, engineering preparation and infrastructure removal.
“We are proud to take on this significant multi-platform decommissioning scope, which reflects the growing demand for our fully integrated services,” remarked Walter Thain, CEO of THREE60. “We have co-created a specific service offering in conjunction with our customer which combines our unique capabilities to responsibly manage these projects, ensuring that we meet the highest environmental standards while delivering safe, efficient and cost-effective decommissioning.
Decommissioning is a key enabler of the energy transition within the UK and a huge export opportunity as other basins globally reach late life.”
Well-Safe Solutions, an international energy transition specialist, has secured two new decommissioning contracts in the UK Continental Shelf for Spirit Energy and an additional global operator.
The workscope comprises approximately 170 days with the Well-Safe Protector jack-up and Well-Safe Defender semi-submersible vessels being used. The two contracts are worth about US$25mn but both include options for a further combined duration of up to 140 days in 2025 and 2026 which could see the total rise by an additional US$50mn.
“Securing these contracts with an array of blue-chip operators – each with their own distinct requirements – demonstrates the flexibility of the Well-Safe Solutions offering in safely and efficiently liquidating ageing well stock,” remarked Chris Hay, Chief Commercial Officer at Well-Safe Solutions.
“Welcoming back Spirit Energy for another mutually-beneficial project is testament to the close cooperation and high performance we achieved together in our last campaign. As the North Sea continues to face political and economic headwinds, it is heartening to see operators securing valuable North Sea assets amidst a backdrop of availability concerns and units departing the region."
Hay continued, “Approximately 60% of the UKCS’ topside and subsea decommissioning is set to occur between 2026 and 2032, making this a key growth industry for the UK and Scotland alike. We are proud to be collaborating with our clients as the industry moves towards a low-carbon future for the North Sea.”
Spirit Energy have selected the Well-Safe Protector having successfully utilised the vessel to decommission 15 subsea wells in the Trees, Chestnut and Appleton fields last year. The new contract will result in the decommissioning of five wells on the York platform, located in Block 47/03a of the southern North Sea, over 97 days. It is planned to commence in Q2 2025, with two optional subsea wells (projected to take approximately 50 days) to be decommissioned in direct continuation or deferred until a later date.
“With York having reached the end of its economic life in the summer this year, Spirit Energy has partnered effectively with Well-Safe Solutions to ensure swift and responsible decommissioning of the asset,” commented Spirit Energy’s Head of Wells, Nicky Riley. “This builds on the success of our previous collaborations on the Chestnut, Trees and Appleton fields. Together, we look forward to continue setting the standard for efficient, responsible decommissioning of assets at the end of their productive lives.”
Elsewhere, the Well-Safe Defender will carry out its decommissioning campaign for an unnamed client. Beginning in March 2025, at least two subsea wells will be worked on across 75 days. This contract also contains two optional subsea well which may be added in direct continuation with the firm scope, plus another three to be executed in 2026.
Well engineering, subsurface and project management specialist, Elemental Energies, has announced a joint venture (JV) agreement with drilling and well services company, Archer, delivering integrated plugging and abandonment (P&A) services to global decommissioning projects.
The long-term partnership will give way to a focused P&A well engineering team that will focus on learning and best practices for P&A design and operations across all well types.
Archer's advanced well services technology and delivery capabilities, along with Elemental Energies' technical subsurface, well engineering and project management expertise, will empower the JV to offer end-to-end well abandonment solutions for platform as well as subsea decommissioning projects. This will deliver integrated planning and execution for large-scale campaigns, supporting operators to maximise efficiency, maintain oversight, and reduce cost. The JV will have the ability to support operators from the earliest project stages, leveraging the strengths of both companies to deliver the most suitable methods and technologies for each project.
Dag Skindlo, CEO of Archer, said, “We’re delighted to deepen our collaboration with Elemental Energies. We acknowledge that some customers are looking to approach P&A differently, and the critical importance of offering a flexible approach to P&A services. This joint venture will help deliver highly efficient well planning and design, with the ability to integrate best in class barrier philosophy and design with deep knowledge of most effective methods to plug and abandon various well types. Ultimately this will help drive down cost of permanent P&A for our clients around the world.”
Mike Adams, CEO of Elemental Energies, added, "There is a close strategic and cultural alignment between our companies, built around a successful track record of working together on joint projects. For P&A to work, it needs long term and highly efficient solutions. This JV will bring that longevity to clients, through a mutual commitment between two long term partners, and a joint venture team that is entirely dedicated to driving efficiency in P&A. This JV partnership is a natural evolution of our relationship with Archer, and we are already actively supporting operators on P&A projects in the North Sea."
As global offshore decommissioning spend is set to rise, the JV aims to offer cost reduction with innovation - essential for advancing decarbonisation. While recognising that P&A needs and preferences vary by region and client, Archer and Elemental Energies are dedicated to supporting these unique requirements, whether through integrated solutions or traditional contracting approaches. This JV represents a commitment to fostering a more efficient and integrated approach to decommissioning across the industry.
Ocean services provider DeepOcean has collaborated with well management and reservoir specialist EXCEED to supply vessel-based well plug and abandonment (P&A) services to the global decommissioning market.
The partnership will offer operators turnkey P&A service for decommissioning projects under a single contract, with services including equipment, planning, execution and close-out, leaving a full audit trail to ensure optimum repurpose and re-use of retrieved assets.
“Compared to rig-based P&A, we believe this partnership can deliver significant time and cost benefits to operators’ decommissioning projects. Our complementary service offering has already proven that it can provide a comprehensive, best in class solution to well decommissioning. We are excited about further developing our relationship with EXCEED,” said Olaf A Hansen, Managing Director, DeepOcean Europe.
The partnership has recently-completed a multi-well, vessel-based P&A campaign on behalf of Serica Energy, saving significant time and costs as well as reduced CO2 emissions compared with rig-based P&A activity.
“By pairing DeepOcean’s subsea engineering competence and diverse global fleet of vessel with EXCEED’S specialist range of well decommissioning expertise, we can offer the international decommissioning sector a world-class vessel-based well P&A service. Forged in the North Sea, we look forward to continuing this relationship by commencing another multi-client, multi-well campaign later this year,” commented John Anderson, Commercial Director at EXCEED.
EXCEED’s dedicated vessel-based decommissioning team provides a fully compliant subsea wellhead removal service. Removing post-decommissioning liability, clients also benefit from cost efficiencies via a campaign approach.
“Our joint competence, technology and assets allow this partnership to deliver safe and efficient offshore operations to clients both here in the North Sea and further afield. We look forward to cooperating with our clients to develop multi-well campaigns that will deliver significant cost and time savings,” remarked Robin Mawhinney, Managing Director of DeepOcean’s UK operation.
Mermaid Subsea Services, a leading international subsea services company, has concluded a 21 well plug and abandonment campaign on behalf of a North Sea operator.
The multi-well campaign was executed using the Island Valiant vessel and was carried out on wells across the Northern and Central North Sea. As the largest contract Mermaid has completed to date, the project spanned two years and created six new jobs in the process.
“This has been a landmark project, not just for Mermaid but also for the wider North Sea decommissioning sector,” remarked Scott Cormack, Regional Director for Mermaid Subsea Services (UK).
“For a company that only entered the UK in 2020 to have carried out, what we understand to be, the largest vessel-based decommissioning campaign in the region ever is a huge achievement, testament to the Mermaid team and further proof that there is space in the market for a new player delivering innovative solutions.
“I would like to thank the whole Mermaid team for playing their part in the successful delivery of this project and to the client for putting their faith in our safe, efficient and cost-effective vessel-based well P&A offering.”
Mermaid is building its reputation in the decommissioning market at an incredibly opportune time given the wave of activity that will be required in the North Sea in the near future. According to the latest OEUK report, operators need to plug 200 abandoned North Sea wells a year in order to stay on top of targets.
Akastor ASA has signed an agreement to acquire all of the interests Mitsui & Co. Ltd holds in AKOFS Offshore, a provider of vessel-based subsea well installation and intervention services to the oil and gas industry.
“We sincerely thank Mitsui for their valuable and good collaboration since 2018,” remarked Karl Erik Kjelstad, CEO of Akastor. “We believe the timing for increasing our investment in AKOFS Offshore is right, as market dynamics within the subsea well intervention and installation sector are increasingly compelling.”
A purchase price of US$22.5mn will see Akastor now hold 75% of the shares in AKOFS Offshore with Mitsui O.S.K. Lines holding the remaining 25%. As part of this development, the two shareholders will negotiate and enter into a new shareholders agreement on similar terms but reflecting the changed ownership.
“We are excited to deepen our commitment as well as to continue the journey together with MOL as partner,” continued Kjelstad. “Together, we remain confident that AKOFS Offshore is well-positioned for continued growth in the years to come and are well-aligned regarding our ownership strategy.”
According to Mammoet, which helps clients with smarter, safer and stronger solutions for heavy lifting and transport challenges, Brent Charlie has been successfully skidded onto the quayside for decommissioning.
Brent Charlie is the last and heaviest topside from the Brent oil and gas field, located 186 km northeast of the Shetland Islands. It is now to follow its siblings – jacket-based Alpha, and gravity-based Bravo, Charlie and Delta – into a decommissioned retirement having been the last one in operation since 2014.
Mammoet has now provided an update on the project, reporting that it has successfully performed the skidding of the 31,000t topside onto the quayside, overcoming complex engineering and safety challenges in the process.
Brent Charlie was required to be removed and transported from the Brent field to the Able Seaton Port near Hartlepool, UK. In order to do so, the company followed a similar process from the previous three Brent topsides.
Allseas used its motion-compensated heavy lift vessel Pioneering Spirit to remove the structure at sea in a single lift and transport it to shallow waters, where the topside was transferred onto Iron Lady, Allseas’ purpose-built cargo barge.
Mammoet had already fitted Iron Lady with skidding equipment (some 45 truckloads of materials), which would be needed to offload Brent Charlie at the port. Mammoet also provided mooring winches for Iron Lady within specific guidelines provided by Allseas on lengths and drum load capacities.
Once the barge had moored at Able Seaton Port and settled into the seabed, the team could determine the starting height of the skid tracks on the quayside and begin laying them down. The topside was skidded over twelve skid tracks, which needed to be perfectly aligned with the skid tracks installed on the barge.
The skidding operation was performed in two stages. First, the topside was skidded five meters to the aft of the barge. Then, after 12 hours to allow for further settling, it was skidded the remaining 130 meters onto the quay, to its final position.
A configuration of 76 skid shoes - divided between the four legs of the platform - and 40 push-pull units were used to skid the topside 15 meters per hour. The combined pushing capacity was 3,320t; the total lift capacity was 51,000t.
Suspended netting was used to collect any falling debris and marine growth that might come away from the structure. All movements were remotely controlled from a control room to minimise the presence of people underneath the platform, and therefore maximise safety.
One of the primary challenges was managing the structures four legs, which cause it to be less stable during skidding. As Richard Verhoeff, Mammoet Sales Director, explained, “When you look at stability, three legs are always stable; four legs are not. You try to keep a three-point suspension when performing a load-in, and still need to achieve that even with four legs. That’s where hydraulic grouping comes in very handy.”
But there can also be some level of deflection between the legs, so the force needs to be able to communicate between the different hydraulic groups.
This is why there were hydraulic cylinders under each leg, and why the cylinders between both pairs of two legs had to be connected – to ensure the pressure on each remained the same.
Despite the various challenges, Mammoet drew from its extensive experience of performing similar operations to successfully complete the task. “We have a pragmatic approach, which is required on jobs like this,” remarked Leo de Vette, Project Manager at Mammoet. “It’s really a team operation, you must do it together. Time is of the essence, so equipment can be moved to the next job. Once the topside is on the barge, there is only one priority – get it off as safely and efficiently as possible.”
Page 3 of 30
Copyright © 2025 Offshore Network
