Optimising Wind Farm Operations with Weather Intelligence

Imagine a severe storm system in the North Sea battering a wind farm, with offshore turbines experiencing excessive structural loads from high winds exceeding 160 kilometres per hour, heavy precipitation eroding multiple blades, and thick cloud cover leading to substantial ice build-up, forcing prolonged curtailment.

 

 

Without accurate weather monitoring capabilities, mechanical strains, physical damage and lost production can result in millions of dollars in repair costs and lost revenue for wind farm owners and operators. A storm like this exposes the critical need for advanced environmental monitoring systems – integrating wind lidars, meteorological sensors and advanced models – to precisely detect and plan for adverse weather events.

 

Reliable atmospheric intelligence ensures that wind farm operators can proactively protect assets, mitigate hazards and maximise performance, even in the most challenging conditions.

 

The Wind Energy Challenges of Weather Variability
As wind energy stakeholders know, increasing atmospheric observations and investing in intelligent turbine controls and O&M are top priorities for further wind industry maturation. The inherent variability of wind and other weather conditions poses multifaceted challenges that can significantly impact the following throughout a project:
⦁ Turbine performance
⦁ Reliability
⦁ Energy production
⦁ Overall profitability
⦁ Safety.

 

Despite wind farms aiming to harness the wind to sustainably power our planet, high winds, gusts, wakes and rapid changes in direction can strain turbine structures, blades and nacelles, accelerating fatigue and increasing the risk of premature failure. Adverse meteorological phenomena reverberate throughout the wind farm life cycle: wind turbulence causes turbine fatigue and extreme loads, nacelle anemometer disturbances lead to yaw misalignment and production losses, and weather events disrupt construction timelines.

 

Since turbines are designed to operate best within specific ranges, any deviation in wind speed or excessively turbulent conditions can force shutdowns to prevent damage. Wake effects caused by turbine–turbine in-farm interactions can significantly reduce overall energy production, with atmospheric stability and turbulence playing pivotal roles in determining the extent of these losses. Finally, ramp events – sudden increases or decreases in wind speed – complicate grid integration and power balancing.

 

Beyond wind dynamics, environmental hazards like icing, lightning, precipitation and hail also compromise turbine availability, necessitating costly curtailments and repairs to mitigate risks and protect assets. Some experts estimate that precipitation droplets cause half of global blade repair costs through leading edge erosion [1], especially impacting today’s larger turbines. Influenced by temperature and humidity, air density fluctuations alter power output calculations, potentially leading to revenue losses for wind farm operators.

 

Turbines are also susceptible to electronic components, control systems and other critical infrastructure damage caused by lightning. Other specific weather conditions like solar radiance, atmospheric stability and boundary layer height influence how the wind behaves on the wind turbine and through the wind farm.

 

Between gusting winds and changes in atmospheric weather, these multifarious challenges underscore the imperative for wind farm operators to adopt holistic strategies that integrate comprehensive weather intelligence into their operations. Accurate weather measurement information enables enhanced profitability with higher production, reliability, predictability and optimal O&M plans.

 

The Power of Integrated Environmental Monitoring
Advanced environmental monitoring systems use cutting-edge technologies, such as wind lidars, meteorological sensors, lightning detection networks and sophisticated data analytics platforms, to provide wind farm operators with a comprehensive view of atmospheric conditions. Improved atmospheric situational awareness helps to maximise energy yields while minimising operational risks and costs.

 

Wind Lidars
Wind lidars are remote sensing devices that use pulsed laser technology to measure wind characteristics with exceptional accuracy and resolution.

 

Vertical profiling lidars, such as the Vaisala WindCube, provide continuous independent monitoring of wind conditions across the entire rotor sweep, including at the unprecedented heights of modern offshore turbines. Real-time data is invaluable for permanent wind monitoring, power performance testing and validating financial models, ultimately increasing efficiency and maximising energy output.

 

Scanning lidars offer full three-dimensional (3D) wind mapping capabilities, enabling the detection of gusts and the generation of minute-to-hour-ahead forecasts. Lidar’s predictive intelligence is crucial for optimising energy generation planning, ensuring a stable supply of electricity and facilitating seamless grid integration. Scanning lidar units can also measure multiple turbine locations at once, creating huge efficiencies in operational assessment to, for example, better understand the turbine wake behaviour.

 

The ‘wake effect’ phenomenon is complex because of the instability, turbulence and turbine-to-turbine wake interactions within wind farms. Consequently, actual measurements are required to validate the modelling for each specific site. Scanning lidar can directly reveal wake effects across an entire wind farm, which can reduce wind speeds by up to 7m/s and annual energy production by 10%.

 

The WindCube Scan’s 3D scanning capability provides both plan position indicator (PPI) scans for horizontal plane monitoring up to 10 kilometres and atmospheric cross-sections in the vertical plane to analyse conditions above the boundary layer. By combining the PPI and vertical scanning abilities, wind farm operators can directly see the wake effects from each turbine propagating across the entire wind farm near the scanning lidar.

 

Nacelle-mounted lidars, like the WindCube Nacelle, provide a wealth of data on wind shear, veer, turbulence intensity and rotor induction effects. This information is invaluable for contractual power performance testing, enabling accurate assessments of turbine performance under varied atmospheric conditions. Additionally, nacelle lidars facilitate in-depth analysis of turbine underperformance, yaw misalignment and nacelle transfer function, empowering operators to proactively identify and address potential issues.

 

Each stage of wind farm development, from wind resource assessment to operational power performance testing and ongoing O&M, benefits from reliable lidar data.

 

Meteorological and Environmental Sensors
Complementing wind lidars are specialised sensors that monitor various meteorological and environmental parameters across the wind farm.

 

Pressure, temperature and humidity sensors enable accurate air density calculations, facilitating corrections for wind speed measurements and power curve assessments. Visibility sensors, built on proven forward-scatter technology, allow intelligent control of turbine obstruction lighting, improving community satisfaction while ensuring compliance with stringent regulations.

Precipitation sensors, including the Vaisala FD70, offer unparalleled droplet measurements, enabling the anticipation and prevention of turbine blade erosion and other forms of premature degradation. Ceilometers combine standard cloud base and ceiling height measurements with depolarisation capabilities, precisely differentiating between particle types, including icing conditions – a critical consideration for wind farm operations in cold regions prone to icing.

 

Lightning Detection and Forecasting
The integration of lightning detection networks and forecasting services further enhances the capabilities of environmental monitoring systems, protecting personnel, assets and revenue streams from potentially catastrophic lightning strikes.

 

Vaisala’s proprietary global lightning detection network offers reliability, resolution and accuracy, providing real-time lightning detection and forecasting capabilities. The service delivers alerts on upcoming storms, with uptime exceeding 99.99% and latency as low as 12 seconds, empowering wind farm operators to implement proactive safety measures and mitigate the impact of operational disruptions.

 

Digital Solutions and Analytics
Harnessing the wealth of data generated by these diverse sensing technologies requires powerful digital solutions and analytics platforms to provide actionable, at-a-glance data analysis and reporting. Integrated digital solutions help to streamline processes and enhance data visibility for turbine performance optimisation.

 

With detailed device monitoring and simple data export functionalities, wind farm operators can quickly access business-critical insights from any device, ensuring efficient collaboration and informed decision-making across their teams. By offering efficient power performance testing analysis, ready-to-use IEC tables and annual energy production calculations, yaw offset and nacelle transfer function calculations, and a proactive display of relevant industry standards, advanced analytical solutions further empower operators to guide power curve verification, IEC compliance and production maximisation.

 

By streamlining analysis, reporting and optimisation across single deployments or entire fleets, advanced software solutions bring all sensor data together, empowering decision makers to identify and address potential performance issues before they become more significant concerns.

 

Integrating Environmental Intelligence for a Better Tomorrow
The true power of these technologies lies in their seamless integration, creating a holistic environmental monitoring system that provides a comprehensive view of atmospheric conditions across the wind farm. By combining data streams from wind lidars, meteorological sensors, lightning detection networks and sophisticated analytics platforms, wind farm operators can unlock a new level of situational awareness and decision support.

 

This comprehensive approach enables numerous benefits for wind turbines and wind farms, including:

With wind energy continuing its rapid expansion, embracing comprehensive environmental monitoring systems empowers wind farm owners and operators to maximise energy yields, reduce operational costs and extend asset lifespans, realising the full potential of wind power.

 

Biography of the Author
Matthieu Boquet is Head of Wind Operations for Vaisala. In this role, he drives strategy and execution for the WindCube lidar suite to meet the industry’s high-level expectations while helping customers continually generate value from their lidars.

 

Further Reading
1. Paquette, J. Blades Global 2021: Erosion. United States. https://doi.org/10.2172/1877843