Function
Resource and metocean assessments provide atmospheric and oceanographic datasets to inform the engineering design of an offshore wind farm, the potential future energy production, and to fully describe the likely installation and operating conditions at the proposed offshore wind farm location.
Who is involved
Resource and metocean assessments are conducted by specialist suppliers contracted by the developer or the state.
Key facts
Wind speed data is required to at least the proposed hub-height of the wind turbines.
Measurement systems are installed at the project location to collect wind data (speed, direction) and other relevant meteorological data (temperature, pressure, humidity).
Metocean buoys are installed in and around the wind farm site to collect metocean data, including wave and tidal characteristics. This information is crucial in establishing whole system dynamics including substructure design types, turbine ratings, vessel types and operations and maintenance (O&M) strategies.
Long-term reference datasets are required to describe the climatology of the proposed site over a longer period typically more than 15 years. Data is usually collected for a period of at least one year to reflect seasonal variation in wind resource and metocean conditions.
These combined data sets are used in the wind farm and system design process, the turbine selection process and to predict the annual energy production (AEP) of the wind farm. Metocean data is also used to inform the vessel selection and operational strategies for the site and is made available to vessel operators and marine planners during the construction and operational phases.
Lidars are a type of remote sensing anemometry devices which use lasers to measure wind speed and direction at up to 300 m above sea level.
Floating lidars are moored buoys on which lidars are mounted. This allows the lidars to be deployed and change location as per demand.
All these sensor types provide data on meteorological and oceanographic conditions at the site of interest. Data loggers provide data storage, processing, and remote communications capability.
Notable differences for floating
Measuring wind speeds at different heights provides critical information about the wind speed profile at the site, aiding decisions about the turbine and floating substructure design. Wind speed data is required to at least 130 m or more above sea level for a 15 MW turbine.
Floating offshore wind farms require the same assessments of wind data but require more metocean data for modelling whole system dynamics.
Floating offshore wind farms are likely to use floating lidars instead of fixed met masts.
