Wave Height Creates Opportunities for CTV Innovation

One of the primary drivers of non-access days at offshore wind farms is wave height, and new generation crew transfer vessels (CTVs) with a larger wave height operating range would be expected to bring non-access days down for sites with higher mean monthly Hs, according to the SPARTA Portfolio Review 2016, launched by ORE Catapult on 28 March.

Image: ESNA
Image from the SPARTA Portfolio Review 2016

The document provides some key insights from the offshore wind farm performance and maintenance data gathered by the system – SPARTA (System Performance, Availability and Reliability Trend Analysis) – which covers 93.7% of the installed capacity of UK operational offshore wind.

Newer wind farms, further from shore, tend to have lower availability but higher capacity factors due to higher wind speeds and more modern turbines. As these new and larger wind farms mature, availability is expected to increase, leading to higher productivity levels, according to the report.

In the summer months, areas with higher wind speeds give higher capacity factors, but this trend is reversed during autumn/winter as adverse weather conditions can mean more non-access days which will impact on a wind farm’s performance. One of the primary drivers of non-access days is wave height, which creates opportunities for innovation in the next generation of crew transfer vessels.

SPARTA is world’s first benchmarking platform for offshore wind farms, sponsored by the Crown Estate and ORE Catapult, with members including DONG Energy, SSE, Centrica, Vattenfall, ScottishPower, Statoil, Statkraft, E.ON, innogy, and EDF Energy Renewables.

“Following a successful pilot phase and first full year of enduring operations, SPARTA has demonstrated how crucial industry collaboration and benchmarking is in continuing to drive down costs and increase production from offshore wind farms,” said Adrian Fox, Chair of the SPARTA steering group.

“Industry members are now working to widen membership and reporting outside of the UK, enabling them to undertake deeper insight and analysis and make more informed decisions regarding offshore wind farm management.”

The SPARTA platform aims to support improvements in the availability, reliability and performance of offshore wind assets, which will drive efficiency improvements, sector innovation, and investment and development.

Operational data is collected across 76 key performance indicators  at system level (from blade to onshore substation), analysed and reported upon monthly, allowing individual performance to be benchmarked against the industry and acted upon by members.