Page 24: of Offshore Engineer Magazine (Nov/Dec 2020)

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FEATURE SUBSEA POWER

Edging towards a

SUBSEA POWERHOUSE

Ten years ago, a future where subsea ?elds and their power-hungry process equipment could be fully electri?ed, enabling long step-outs to tap remote reserves with lean new infrastructure architectures, lit the fuse for a spate of investment in subsea power distribution.

By Elaine Maslin he result, following at least two major joint industry projects (JIP) and tens of millions of dollars of invest- ment, is that subsea power distribution is now a ready

Ttechnology, waiting for its ?rst application.

GE Oil & Gas (as was) quali?ed a subsea power distribu- tion system back in 2016, including variable speed drives (VSDs), switchgear, and power protection, based on existing components marinized in pressure tolerant housings. The sys- tem was developed to provide power over a 120 km distance to the Ormen Lange subsea compression project in Norway, only for Shell to decide against the project.

This year, ABB quali?ed its subsea power distribution sys- tem – complete with transformer, VSD, switchgear, and con- trols, and Siemens is moving closer to qualifying its system.

Others are moving in on the patch with smaller, less com- plex systems, including TechnipFMC, while Baker Hughes’

Modular Compact Pump aims to come with integrated VSDs, mitigating the need for full-on ‘type-3’ (i.e. supply, transmis- sion, and distribution).

The goal is to provide power, ranging from 750 kW to more than 11MW, to subsea systems, from pumps to compressors.

This includes the power equipment and electronics re- quired, to avoid having to make brown?eld modi?cations on existing topsides and/or enable entirely subsea developments to shore. The bene?ts are touted as a more scalable and ?ex- ible architecture.

However, the much longer step-outs that have been target- ed have bigger challenges, in terms of ?ow assurance, points out Bjørn Søgård, Segment Director, Subsea, at DNV GL.

Potential candidate projects like Chevron’s Janz-Io subsea compression project, in 1300m water depth 200km offshore

Australia, are targeting topside power and controls.

Source: Siemens 24 OFFSHORE ENGINEER OEDIGITAL.COM