Acoustic Tech Help Offshore wind industry
Nortek supports ocean weather research and consulting company Partrac to provide developers of floating wind farms with detailed and accurate ocean weather data at potential development sites. With Acoustic Doppler Current Profiler (ADCP), Partrac is able to expand its capabilities and adapt to increasingly complex offshore environments.
To date, virtually all offshore wind energy produced in the world comes from turbines located in waters less than 50m deep, where the turbine tower can be directly attached to the seabed. But with the rapid growth in demand for wind power – and the filling of suitable sites with shallow water in some places – the industry is now looking to move to deeper water. However, these environments create a whole new set of challenges for developers.
The existing monopile or gravity designs typically used for shallow water wind farms, which involve securing the tower directly to the seabed, are not as simple or cost effective to deploy in deep water. As seen in other industries, it may be more cost effective and practical to install deep water wind turbines on floating structures attached to the seabed, potentially opening up the ocean much more to wind farm developments.
Despite the advantages of using floating platforms, offshore wind developments remain complex, so it is crucial to obtain the most accurate data on weather-ocean conditions at the proposed sites. Wind resources may be abundant, but ocean conditions in deeper water present a different set of challenges than shallow water close to shore – and they require different tools and expertise to analyze them.
- The future: floating offshore wind farms
For Partrac, one of the UK’s leading geoscience and meteorological survey consultancy services, growing interest in floating offshore wind farms means the company is increasingly in demand for data that developers can use for site characterization and modeling in waters deeper than standard.
ADCPs have long been a crucial part of Partrac’s toolbox for building detailed profiles of current and wave movements around wind farms. These instruments provide very precise profiles of water movement by using the Doppler effect to measure the displacement of sound waves reflected from particles at different depths through a water column; above all, they are also able to measure the climate of the waves.
But moving to deeper waters now requires a longer range ADCP solution.
The Nortek team was well placed to help with this change, having provided ADCPs and expertise to Partrac for many years. Historically, shallow water wind farm feasibility studies have been performed using Nortek’s higher frequency, shorter range Signature and AWAC instruments. But collecting data in deeper waters requires equipment designed to withstand and measure extreme wave regimes, while accurately measuring currents from the surface to the nearby seabed at greater depth.
With these challenges in mind, Nortek was able to supply Partrac with its ADCP Signature250 and the accompanying underground buoy. The instrument allows users to measure directional currents and waves up to 200m for current profiling and 150m for wave height and direction, making it the preferred choice for wind turbine sites in deeper waters.
“We needed a deeper water instrument that could still measure both current profiles and wave climate. So far, the Signature250 has provided exceptional data, ”says Pete Wilson, Director of Operations at Partrac.
“We consider Nortek’s instrumentation design and technology to be very progressive and responsive to developments in information technology in general,” he says. Oceanographic deployments in harsh environments are inherently risky business, but these risks must be minimized. Sensors and ancillary equipment must be robust, reliable and easy to retrieve. Lost or faulty sensors mean lost data and potentially lost business for companies like Partrac, which are required to deliver accurate data to their customers on time.
This was Partrac’s first deployment of the Signature250 in the configuration used. Nortek therefore ensured that the team was well supported with advice, as well as providing Partrac with feedback from others operating in similar environments.
Pete Wilson said he hopes his company’s work will help advance the offshore renewable energy sector in Europe.
“The data and advice we provide is critical both at the initial stage of site feasibility and at the consent stages and later during the engineering process,” he says.
Floating wind is a niche technology, but it is rapidly gaining ground. The GWEC estimates that the floating wind power generation capacity in the world could reach more than 6 GW by 2030, compared to less than 0.07 GW in 2019. And the growth could be much higher than that if development costs fall. – a probable prospect, as the efficiency and size of the number of turbines increases and companies gain more experience in the construction of floating wind farms.