US major Chevron is still looking for a less costly solution for developing its deepwater Rosebank oil discovery west of Shetland, while FEED work continues.

DI hears that the operator is still trying to find a cheaper way of tapping the estimate 240 MMbbl of oil discovered at Rosebank after deferring the UK project earlier this year due to high costs. “The review of the economics is progressing, and the co-venturers focus continues to be about making the right decisions that are not driven by schedules and timelines,” an operator spokeswoman told DI.

After the Rosebank discovery well and a sidetrack, 213/27-1Z, drilled in 2004, the field was estimated to contain up to 240 MMboe of recoverable reserves. Up until last year Chevron was planning to tap the find via an FPSO but it then put the brakes on in November, saying Rosebank was no longer considered to be economically viable.

As part of the FPSO-based development, for which Hyundai secured a US $1.9 billion EPC contract to build a turret-moored FPSO with storage for up to 1 MMbbl of oil, Wood Group Kenny was also providing FEED studies for a related 236 km (147 miles) gas export pipeline from Rosebank via other infrastructure to the St Fergus gas terminal.

Also as part of the original development plan Dolphin Drilling was awarded a 5-year $1.1 billion charter for a newbuild harsh-environment semisubmersible rig named the Bollsta Dolphin. No changes have been made to the Bollsta Dolphin contract, the Chevron source said. Rosebank lies in a water depth of 1,115 m (3,623 ft).