Tolmount Main gas field, one of the biggest undeveloped gas discoveries in the Southern North Sea, UK, is set to break ground for development by the end of 2018.
The offshore gas field is jointly owned by Premier Oil (50%), who is also the operator, and Dana Petroleum (50%).
First production from the field is expected in the fourth quarter of 2020. The peak production from the gas field is estimated to be 300 million metric cubic feet of gas a day (mmscfd), while the cumulative production over its project life is estimated to be 500 billion cubic feet (bcf) of gas.
Tolmount Main gas field location and reserves
Located 64km off the coast of Shetland in Yorkshire, Tolmount Main is the biggest gas field in the Greater Tolmount Area in the Southern Gas Basin.
Tolmount Main is estimated to hold 540bcf of recoverable gas resources. The other gas fields in the Greater Tolmount Area are Tolmount East and the Tolmount Far East, which are estimated to contain 220bcf and 150bcf of gas respectively.
The total recoverable gas resources at the Greater Tolmount Area are estimated to be up to one trillion cubic feet (tcf).
Tolmount Main gas field development details
The Tolmount Main gas field development will comprise four initial production wells to be drilled from a heavy-duty jack-up mobile offshore drilling unit (MODU), and a minimum facilities platform (MFP) with processing facilities to remove water from the well flow.
A 47km-long and 20in diameter subsea pipeline will be laid to export the produced gas and condensate to Centrica’s Easington terminal located in East Yorkshire, for further processing.
The Tolmount offshore development will help extend the operational life of the Easington gas terminal at least until 2030.
Premier Oil will invest $120m towards the project management and development drilling costs of Tolmount Main gas field.
Dana Petroleum and Humber Gathering System, the infrastructure joint venture partners for the project, will jointly finance, construct and own the offshore platform and the export pipeline, as well as bear the costs for upgrades to the onshore terminal.
Humber Gathering System is a member of the Central Area Transmission System (CATS) Management Limited (CML) group of companies.
Contractors involved with Tolmount Main offshore project
Rosetti Marino was awarded the engineering, procurement, construction, installation and commissioning (EPCIC) contract for the minimal facilities platform for the Tolmount Main gas project, in August 2018.
Rosetti Marino will construct the platform at its PiomboniYard in Marina di Ravenna, Italy.
Centrica Storage was awarded a contract worth £120m ($153m), in August 2018, to process the gas produced from the Tolmount Main gas field, at its Easington facility.
Shearwater GeoServices was contracted in May 2018 to carry out a high-resolution 3D seismic survey over the Tolmount field area, using its high-capacity 12 streamer seismic vessel Polar Duchess.Saipem was awarded the EPCI contract for the pipeline for the Tolmount Main development, in August 2018.
Wood Group was awarded the front-end engineering design (FEED) contract for the platform topsides as well as other subsea structures for the field development, in April 2017.
Costain was awarded the FEED contract for an onshore plant to receive and process gas from the Tolmount field, in September 2017.