Offshore Engineering
NEP Completes Two Wells for Its Expansion-Store Appraisal
NEP has completed its two-well appraisal across CS006 and CS007. The results now inform expansion capacity, well duties and a programme through concept selection, planned 2027 FEED and a planned 2028 investment decision.
Two wells complete the appraisal campaign
Northern Endurance Partnership has completed its two-well appraisal campaign across Southern North Sea storage licences CS006 and CS007. Its 27 October update identifies the completed wells as C43/30-2, known as BC39-1, and C44/27-3, known as BC37-1. Evaluation and characterisation will continue through 2026 and 2027, with front-end engineering design planned for 2027 after concept selection and a final investment decision planned for 2028. [1] The programme combines the wells with geophysical surveys, environmental assessment and offshore studies. The new results feed into an expansion concept whose well count and subsea connections were set out in NEP's March 2026 System Development Statement. That document makes the expansion capacity and scope contingent on the appraisal analysis and an additional investment decision. [2] The March concept envisages four injection wells for CS006, covering the BC40 and BC39 storage sites, with a connecting pipeline to Endurance. CS007 would cover BC37 and BC36, with three injection wells. These are the development statement's expected configurations. [2, section 4.2]
Well duties shape the future subsea system
The well configurations give the appraisal work an infrastructure consequence. The usable injection rates and pressure limits determine the flow each storage system can receive. Detailed design then needs the well duties, connection pressures and operating cases that the pipelines, manifolds and controls must accommodate. A change in the usable storage envelope can change the equipment duty and allocation of flow. NEP's June account of the first well reported around 500 metres of sealing rock above a 250-metre Bunter sandstone interval at BC39. It described the results as preliminary and said the collected data would support further technical appraisal. Those thicknesses concern BC39; the October completion announcement brings the second well and wider studies into the evaluation programme. [3]
Evidence conclusion
Evaluation leads into concept selection
For offshore contractors and engineering suppliers, the next consequential development is the selected expansion configuration: the receiving stores, injection duties, subsea connections and their installation sequence. The March statement also identifies potential later work on legacy-well remediation, detailed design, permitting and licensing. [2] This expansion has its own development and investment sequence alongside the existing Endurance construction programme. NEP's July construction announcement describes the separate 149-kilometre offshore pipeline from Teesside. The expansion-store programme now has completed appraisal wells and a stated route through evaluation, concept selection, FEED and investment decision. [1, 4]
Outstanding evidence
- Combined appraisal interpretation and selected expansion configuration
- Injection duties, operating pressures and subsea connection scope
- Concept-selection outcome,2027 FEED and 2028 investment decision
Subject index
Related subjects
These subject pages bring together related projects, technical articles, reports, and evidence methods.
Sources used 4
- NEP, completed appraisal campaign, 27 October 2026 Northern Endurance Partnership, 27 October 2026
- NEP, System Development Statement, March 2026, sections 4 and 4.2, printed pages 20-22 Northern Endurance Partnership, March 2026 edition; uploaded April
- NEP, preliminary first-well results, 11 June 2026 Northern Endurance Partnership, 11 June 2026
- NEP, offshore construction launch, 23 July 2026 Northern Endurance Partnership, 23 July 2026