Client – RWE Renewables UK

Project Overview

The London Array project in the outer Thames Estuary is currently the world’s largest consented offshore wind farm. The London Array met mast is approximately five miles out to sea adjacent to one of the largest on-going construction projects in the UK, installing 175 wind turbines. At 1,000MW, the wind farm could eventually power up to 750,000 homes.

Dulas has been involved with the London Array project installing wind monitoring instruments and maintaining the met mast since 2008. Dulas regularly visit the mast to replace instrumentation, inspect the tower and more recently, to install a tide level sensor.


The installation of the new calibrated instruments requires two people to climb up to each instrument, the highest being 80m from sea level.

The data from the instruments is then recorded in the CR 3000 data logger on the platform of the mast and data is then downloaded remotely via GSM modem. In addition to this, some data is sent every ten minutes via satellite communications to the site operations team. The data is used both by the construction team for checking current wind speeds and by the Project Owner’s data analysts.

“London Array have worked with Dulas for numerous years, and they have provided excellent and cost-effective service in maintaining our met mast. Both the offshore and onshore teams have worked hard to deliver inspection and maintenance services, working with us to find the most optimal solution to implement offshore. We look forward to working more with Dulas ongoing”

Alex Hoss, RWE Renewables UK

Developing and operating an investment-grade asset depends on robust, accurate and bankable data. Proven and dependable data from traditional metmasts have been the cornerstone of the modern wind industry since the late 1980s. Understanding wind flow at different heights using advanced anemometry, is at the core of Dulas’ DNA since 1988, when we installed our first anemometer and data logger system at the Cemmaes wind farm, Wales.

Find out more about Dulas’ Wind Monitoring turnkey services for met masts here