Targeted inspections of wind turbines with optimized lightning detection

Lightning strikes pose a serious threat to wind turbines, regardless of the season. They not only cause structural damage to rotor blades but can also lead to prolonged downtime and significant revenue losses.

 

In this article, we will show you how optimized lightning monitoring enables more targeted inspections of wind turbines, helping you save time and increase efficiency.

Lightning strikes are not limited to a specific season. They occur year-round and pose a constant threat to wind turbines. According to the latest Annual Lightning Report from Vaisala Xweather, a staggering 2.2 billion lightning strikes were recorded worldwide all year around in 2024.

 

However, not all lightning strikes are the same. They can be categorized into different types: cloud-to-ground (CG) lightning, ground-to-cloud (GC) lightning, and cloud-to-cloud (CC) lightning. Cloud-to-ground lightning is classified as downward lightning because its discharge travels from the cloud to the earth. Ground-to-cloud lightning, also known as upward lightning, presents a significant challenge for wind turbines. Due to its long-lasting continuous current, it can be far more destructive than downward lightning. Cloud-to-cloud lightning occurs within a single cloud or between multiple clouds.

 

Moreover, peak current intensity can vary depending on the season. Winter storms not only bring snow and ice but also lightning. While less frequent than summer lightning, winter lightning can have peak currents up to 10 times stronger than typical summer strikes. This makes it particularly hazardous for rotor blades in wind turbines, especially when these strikes go undetected.

Continuous monitoring of wind turbines and lightning detection are essential for identifying lightning strikes early, conducting targeted inspections fo wind turbines, and making timely decisions.

 

Our advanced lightning monitoring system, :EVENT LIGHTNING, provides wind farm operators with real-time information on when and where their turbines have been struck by lightning. This technology is further enhanced with Add-On Xweather, a software upgrade to the existing :EVENT LIGHTNING product. Developed in collaboration with the renowned U.S.-based company Vaisala Xweather, this add-on integrates data from the Global Lightning Dataset (GLD360) and the National Lightning Detection Network (NLDN). As a result, it delivers comprehensive insights into lightning events, including signal strength, polarity, event type, distance, and rise time.

 

By combining these technologies, operators gain even more precise lightning analysis, enabling them to optimize their inspection and maintenance strategies for wind turbines worldwide, saving time and increasing overall efficiency.

Add-On Xweather integrates data from two state-of-the-art lightning detection systems:

• GLD360 by Vaisala Xweather – a global lightning detection network that provides high-resolution, real-time lightning data.
• National Lightning Detection Network (NLDN) – a well-established and proven system for monitoring lightning events across North America.

 

By leveraging these data sources, the add-on delivers comprehensive insights into lightning events, including:

• Lightning signal strength and polarity
• Event type (cloud-to-cloud or cloud-to-ground lightning)
• Rise time and energy intensity
• Timestamp of the event

 

These precise insights enable targeted inspections and prioritized maintenance of affected wind turbines, helping operators optimize efficiency and reduce downtime.

Wind farm operators, especially those experiencing frequent lightning strikes, face several key challenges:

• Avoiding un-necessary inspections: Not knowing which wind turbine has a lightning strike and avoiding inspecting turbines with no lightning strike.
• Invisible damage: Not every lightning strike causes immediately visible damage, but it can lead to long-term structural issues.
• Unplanned downtime: Lack of accurate, real-time information results in inefficient maintenance processes and unnecessary downtime, leading to significant costs.
• Expensive repairs: Undetected lightning damage often results in costly repairs that could have been prevented with early detection.

 

With EVENT LIGHTNING and Add-On Xweather, operators gain more precise, real-time data, enabling targeted inspections of wind turbines. This saves time, reduces maintenance costs, and maximizes energy production.

 

Read more about the key-questions you should ask yourself when deciding on a lightning detection system.

Integrating both systems provides numerous benefits:

• Avoiding un-necessary inspections: Avoiding inspecting turbines with low intensity lightning and/ or no lightning strike.
• Early detection of lightning damage: By directly capturing lightning strikes with :EVENT LIGHTNING and combining it with comprehensive geographic and lightning data from Xweather, operators can not only detect strikes in real time but also enhance their emergency response and asset management.
• Optimized maintenance strategy: Operators can inspect affected turbines more efficiently, allowing for prioritized and optimized maintenance planning.
• Reduced downtime: Faster and more precise maintenance scheduling helps minimize turbine downtime.

Many operators rely on general weather services or lightning detection systems with limited range and resolution. The key difference with :EVENT LIGHTNING and Add-On Xweather lies in its direct integration of lightning events with turbine data. While conventional weather services provide only broad lightning activity reports, our system enables precise mapping of strikes to individual turbines and delivers detailed analyses of each event.

With :EVENT LIGHTNING and Add-On Xweather, wind turbine operators can optimize turbine inspections with precision. This not only saves time and costs but also extends the lifespan of their turbines and maximizes energy production.

 

Sources:

• Vaisala Inc.: A Multiyear CONUS-Wide Analysis of Lightning Strikes toWind Turbines, https://www.researchgate.net/publication/388836889_A_Multiyear_CONUS-Wide_Analysis_of_Lightning_Strikes_to_Wind_Turbines, 09/2024
• Annual Lightning Report of Vaisala Xweather: https://www.xweather.com/annual-lightning-report