Atlantic Alliance: The Next Generation Tension Leg Platform

Abstract

Abstract Since 1990, the technical and commercial environment in the oil and gas industry in the U.K, has seen a step change in relationships. This has contributed to significantly improved development cost and time parameters. By harnessing the potential energy and expertise in the market place, many more marginal fields are now below brought into production. This paper gives an insight into the exceptional results that can be achieved by bringing together complementary skills and expertise, having a common vision for the future. Introduction The Atlantic Alliance (AA) is a joint venture formed by the AMEC and Iaing groups from the U.K. and the Aker group from Norway. AA came together in late 1994 for BP's prequalification process for deepwater solutions for the UK North Sea and Atlantic waters. 1 Msprocess resulted in AA being rated as 'best in class' by BP for a concrete tension leg platform, AA were then invited to participate in a design competition against other consortia with alternative solutions, for the second West of Shetlands development known as Atlantic Frontier Programme II (AFP II). The AA proposals were based on a down scafed version of the first concrete TLP by Aker for Conoco's Heidrun field in Norway. A step changein costs and schedule were achieved but not sufficiently to win the project. BP and AA however, felt that the relatively short bidding period had not given enough time to fully release the potential of the concrete TLP solution. A joint workshop and subsequent study brought together a selection of key individuals with Gulf of Mexico, Norwegian and U.K. related experience to explore options to radically reduce time and cost parameters. By Christmas 1995 this study work had delivered the potential for a major breakthrough for the next generation TLP. At the time of writing, this is now moving into the full concept development phase ready for its first project. Study Process and Result Expectation For the TLP to be retained in the development matrix as a concept of opportunity, a step change in competitiveness (versus the FPSO) must be realised. Expectations were that through this work, a concept would be defined that will realise the requisite level of step change througha CAPEX reduction of 25% from AFP IIa delivery programme reduction from commitment to 24 months from the AFP II schedule of 30 months, i.e. 20%,an installation window that is not seasonably limited, i.e. similar to a FPSO Result The study work delivered a step change opportunity. The New Generation TLP has taken us beyond our expectations with:an estimated 30% reduction in CAPEX,a sub 24 month programme from commitment anda weather window of 12 months - in line with an FPSO.