Tyra, the hub of Denmark's gas production, is set to be shut down this week as operator Total gets ready for a multi-billion-dollar project to remove eight ageing platforms and redevelop the North Sea field in just under three years.
More than 90% of Denmark's natural gas production is processed at Tyra, but because of depletion of the reservoirs underground, two processing platforms and six wellhead platforms have been sinking into the seabed to the point that they are becoming unsafe.
Last week, Total flew Danish reporters and Upstream’s correspondent out to the Tyra East platform, which has produced gas for Denmark for more than 35 years.
Having landed at the jack-up rig Maersk Guardian, the bridge over to the platform has a noticeable slope.
“You probably noticed that you were walking downwards. The difference is six meters. This is what we have lost over the years since the reservoir rocks have become more compact after 35 years of production,” says Patrick Gilly, managing director of Total E&P Denmark.
Large waves
The Gyda platform decks are now only 15 metres above the sea surface, and with further sinking large waves could threaten equipment and personnel, Gilly explains.
Because of the subsidence, Total and its partners in the Danish Underground Consortium (DUC) had to make a decision for the future of the Tyra field, and together with Danish authorities they opted to rebuild the country's most important field.
DUC, a joint venture between Total, Noreco of Norway and the Danish state-owned North Sea Fund, decided to revamp the field at a cost of Dkr21 billion ($3 billion) with the newest technology available, allowing efficient gas production from a modern facility, according to Gilly.
“We committed to rebuild, and we are sticking to our commitment. There is still a lot of gas left to produce," Gilly says.
"The redevelopment will enable Tyra to continue operations for at least 25 years, and at peak production, the new Tyra gas field will provide enough gas to supply what corresponds to 1.5 million Danish homes.”
The new Tyra is expected to deliver about 60,000 barrels of oil equivalent per day at peak, and it is estimated that the redevelopment can enable production of more than 200 million barrels of oil equivalent.
Top-notch technology is key to the new project, says Gilly.
“We are building separate platforms for processing and living quarters," he says.
"The large processing platform will be packed with a lot of technology. Personnel will have iPads with access to live data on performance, flow rates and condition of equipment.
"A lot of data will be sent via a fibre-optic cable to the operating centre onshore.”
According to Gilly, the new high-tech Tyra will be a state-of-the-art production and export centre that will secure Danish and European gas supply for many years to come, and thereby support the transition towards a low-carbon energy future.
The redevelopment ensures that Denmark will continue to have a critical piece of gas infrastructure in place, which will also enable future production of oil and gas volumes from new projects in the DUC license area as well as from third-party projects.
Energy efficiency
The new Tyra will support Total’s vision for better energy efficiency and more sustainable operations, says Gilly.
“It will be built to minimise the climate and environmental footprint from our Danish North Sea operations," he says.
"We expect to reduce the carbon-dioxide emissions from Tyra by 30% as a result of the new design, which will lower the level of flaring and improve energy efficiency."
Boosting gas production is a key element in Total’s strategy to combat climate change, Gilly says.
“Gas is the obvious bridge in the energy transition, and we want to make natural gas a bigger part of our oil and gas mix, upwards of 60% within 20 years. The redevelopment of Tyra is an important part of reaching that objective,” he says.
Through new development projects and third-party tie-ins, the redeveloped Tyra field could be a catalyst for extending the life of the Danish North Sea — not just for Total and the DUC, but also for Denmark.
“The new infrastructure can enable operators to pursue new gas projects in the northern part of the Danish North Sea, where the most recent development, Tyra Southeast, delivered first gas in 2015 and is producing above expectations,” says Gilly.
