Raising Tyra

On behalf of the Danish Underground Consortium (DUC), Maersk Oil worked with the Danish Government to find an economically viable solution for the redevelopment of the Tyra field in the North Sea. It shows that with the right investment and expertise, there is still plenty more potential for extracting hydrocarbons from mature fields.

Tyra

Redeveloping Tyra

  • Today, the Tyra field consists of two main centres: Tyra East and Tyra West. Tied into the centre are 5 unmanned satellites: Tyra Southeast, Harald, Valdemar, Svend and Roar
  • The unmanned satellite platforms in the area have not been affected by subsidence, and will therefore not be redeveloped. Production from the satellites will be temporarily shut down during the redevelopment
  • Production from Tyra is expected to be shut-in temporarily in December 2019 to enable the removal, renovation and re-development of the facilities
  • Once its redevelopment has been completed in 2022, Tyra will again play an important role in the reliable and secure supply of gas to Denmark
  • The redevelopment of Tyra is dependent on the Danish Parliament passing the bill on the agreement made (expected in October 2017) and on Maersk Oil taking a final investment decision on the project, which is expected by December 2017

How do you solve a problem like an offshore platform sinking into the seabed?

The short answer is that it takes a lot of planning and expertise, and a strong partnership between operator, DUC partners, government, suppliers and research institutions. But that only begins to tell the tale.

“The current gap between the platform and sea level is about 15 metres, and with wave heights reaching 10-15 metres during severe winter storms this naturally poses a safety risk, which Maersk Oil as a prudent operator needs to mitigate,” explains Morten Hesselager Pedersen, who is the Head of Tyra Future Development.

Oil and gas have been produced in the Danish North Sea for half a century. There is still a lot more that could be extracted, but the right investment and expertise are needed to do so.

Maersk Oil is the largest oil operator in Denmark and its biggest partnership is the DUC, where 85% of the country’s oil and 97% of its gas exports stem from. They have reached an agreement with the Danish government that provides terms that will enable the partners to proceed with a full re-development of the Tyra facilities. This in turn will pave the way for future oil and gas investments in the Danish North Sea and protect jobs within the industry.

The re-development will restore the functionality of the current facilities, including the gas processing hub and five surrounding satellite fields, and therefore ensure continued production from the Tyra field. The new facilities could also enable future new production of oil and gas from the northern part of the DUC license area as well as third party projects.

“It is of course a great and very exciting project to be heading,” Pedersen says. “It will benefit not only Maersk Oil and the DUC, but also the Danish state as it protects jobs, security of energy supply and continued tax payments. It is a humbling experience and one which I am very proud to be a part of.”

A brighter mood

The city of Esbjerg, on the west coast of Jutland in Denmark, is all about oil and gas, and for Mayor Johnny Søtrup, the agreement on Tyra’s future is vital – and he can already sense a more cheerful atmosphere about the place as a result.

Not only will it benefit Maersk Oil and the DUC, it will also be of benefit to the Danish state as it protects jobs, security of energy supply and continued tax payments. It is a humbling experience and one which I am very proud to be a part of.

Morten

Morten Hesselager Pedersen, Head of Tyra Future Development

The Tyra field

  • Tyra is Denmark’s largest gas field and its facilities are the processing and export centre for all gas produced by the Danish Underground Consortium (DUC). More than 90% of Denmark’s gas production is processed through the facilities
  • Tyra East and Tyra West also function as the hub for a number of smaller facilities in the Tyra field. This includes the neighbouring unmanned facility, Tyra Southeast, which was extended in 2015
  • The Tyra field is operated by Maersk Oil on behalf of the DUC, a partnership between A.P. Moller -Maersk (31.2%), Shell (36.8%), Nordsøfonden (20.0%) and Chevron (12.0%)

With the agreement in place, the port will remain the central hub of offshore activity in the Danish North Sea and many local supply companies expect growth due to the redevelopment. There is also a greater willingness to invest in the future, Søtrup says.

“The economic benefits will not only be of crucial importance to the oil and gas companies, but also the many, many businesses which supply goods or services to the sector,” he says. “Our hotels, restaurants and shops would have suffered a decrease in activity. Right now, we are instead experiencing an increased interest from companies outside Esbjerg, which plan on becoming part of the supply chain to the offshore industry.

“The outlook is brighter than it has been for some time, and this is reflected by the general mood in the city.”

Complex challenge

In order to maximise the potential that the reservoirs in the Tyra field still represent, a full re-development of the facilities is needed. This means extending the lengths of the jackets – the steel frame which supports the deck and topside of a fixed offshore platform – at six wellhead and riser platforms by more than 10 metres and then replacing the topsides.

One of the most critical aspects will be to make sure that the new topsides for the wellhead and riser platforms are a perfect fit with the extended jackets, and that the jackets are capable of carrying the additional weight and resisting the expected wave impact.

The current Tyra East and Tyra West processing and accommodation centres will be replaced by one new processing centre and one new accommodation centre. Last, but not least, about 50,000 tonnes of old facilities will be decommissioned and removed.

“A project this size is naturally quite complex. It will also be the first time in the Danish North Sea that we will be decommissioning a platform so that in itself is a challenge,” says Pedersen. “That being said I am confident that we have what it takes to successfully carry this project through to completion and I look forward to the exciting challenge.”