Wind Turbine Drone Inspection: A Guide

As renewable wind power continues to grow in demand, wind turbine drone inspection will play a critical role in prolonging the service life of wind farms. 

Wind turbines require routine maintenance and inspections to prevent wear and tear, which can reduce the efficiency and lifespan of a turbine’s structural components. As part of the maintenance process, a wind turbine drone inspection can identify blade delamination, core defects, internal component failure, and other key defects. 

Additionally, a drone wind turbine inspection produces more detailed data than traditional inspection methods and can significantly speed up the inspection process.

In this guide on wind turbine drone inspection, we'll take a look into the following topics:

What Are the Traditional Methods Used to Inspect a Wind Turbine? 

Wind turbines continue to grow in size, with the average land-based unit standing over 200 feet tall. And these increased sizes present more challenges to safety and inspection processes. 

During a traditional wind turbine inspection, a crewed inspection team known as rope access technicians will use a rope and tether system to climb inside and outside the turbine structure. While climbing they will conduct a visual inspection, looking with their naked eye for any anomalies that indicate the presence of a defect that might require maintenance.

In addition to visual inspections, rope technicians also perform a series of knock tests on wind turbine blades to estimate their structural integrity. While these methods do work, they are inefficient, dangerous, and more costly than using a drone to collect visual data. (A drone can’t replace a person for doing knock testing—not yet, anyway.)

What are the downsides of traditional wind turbine inspections? 

• Wind turbines must be shut down for hours during a traditional inspection, downtimes that result in a loss of income and energy

• A lot of equipment and setup time is required to reach all the areas of the structure. 

• Visual and sound tests cannot provide the data acquired from advanced sensing equipment used on drones. 

• Manual inspections are very dependent on weather conditions. 

Learn more about wind turbine inspections and how they’re performed.

How Is a Drone Used to Inspect a Wind Turbine

The wind energy industry is quickly integrating wind turbine drone inspections to increase inspection speed, improve accuracy, and reduce the dangers to technicians. 

A wind turbine is inspected in a two-part process, regardless of the inspection method. Each blade features dual chambers constructed of a composite laminate material. Internally, the interior of each blade needs to be analyzed.

Instead of physically crawling into each blade, specialized indoor drones like Flyability’s Elios 3 (shown below) can navigate the chambers and quickly retrieve high-resolution imagery and data.

Using a drone, inspectors can identify missing bolts, lightning damage, and other defects that threaten the functionality and longevity of the turbine.   

What are the steps in performing an internal wind turbine inspection? 

1. Equip the drone with a UNISET device which allows inspectors to know exactly where the drone is located within the blade. The location information is crucial for marking areas with defects. 

2. Once the drone is equipped, the pilot will enter the manhole, giving them access to the chamber that holds all three blades. 

3. From here, the drone is flown into each blade, collecting the visual data that will be reviewed as a part of the wind turbine drone inspection. 

If the drone is equipped with geolocational technology then the first step may not be necessary. 

For example, Flyability’s Elios 3 carries a LiDAR sensor that allows it to create 3D maps in real time, and these maps contain geolocational information that inspectors can use to pinpoint the location of defects found while collecting inspection data.

Benefits of a Wind Turbine Drone Inspection

Inspections in wind turbines can present many dangers to workers, especially as they vary in height, construction, and operational environments. 

Offshore wind turbine inspection are even more dangerous, presenting unpredictable weather conditions that increase the risks to inspectors—not to mention the journey to get there and the fact that offshore wind turbines are taller than their land-based counterparts. 

Given these inherent dangers and challenges, more wind farms see the value of land-based wind turbine drone inspection and offshore wind turbine drone inspection.  

Reducing safety hazards while simultaneously increasing inspection speed and accuracy is more important than ever, as some wind farms have several hundred wind turbines that must be inspected two to three times a year. The work load quickly adds up when you consider that each unit has three blades with dual chambers. 

As the push for renewable energy continues, traditional inspection methods will struggle to keep up with the global demand.

Here are the primary benefits of wind turbine drone inspections: 

• Safety. Workers do not have to enter the confined space where the blades are housed or work at height for inspectors to collect the data they need.

• Savings. Wind turbine drone inspections are less expensive than crewed inspections. 

• Efficiency. Drones streamline the data collection and review process.

• Better data. High-resolution images can identify defects the human eye can't detect and new drone sensors can expand inspection opportunities.  

• Speed. A drone can cut the time needed for a wind turbine inspection in half while covering more area than rope technicians. 

Of course, safety is the biggest benefit overall in using a drone to collect inspection data inside a turbine instead of a person.

The most profound concern is the height workers are exposed to when drones are not used for inspections. Instead of rigging ropes and tethers, a wind turbine drone inspection eliminates the need for complex equipment and enhances safety. 

Mechanical and physical hazards such as noise, temperature, vibration, electrical, moving parts, inadequate lighting, entanglement, slips, or falls are all also potential dangers when working in a wind turbine, and all of these can be avoided by using a drone.

What Drones Are Best for Wind Turbine Inspections? 

Flyability’s Elios 3—Internal Drone Solution

In the past, the inspection process via drone was limited to exterior applications only. However, the Elios inspection drones from Flyability have revolutionized how a wind turbine inspection is performed.  

[Related read: Internal Wind Turbine Blade Inspection With Elios 2 Cuts Inspection Time in Half] 

The Elios 3 turns the unreachable into a digital landscape that creates real-life, actionable insights. Its collision-tolerant caged design and advanced autonomous FlyAware software allow you to complete a wind turbine drone inspection easily. 

The Elios supports work in dark areas with a dual thermal 4K camera and 16K lumen dust-proof lighting system, allowing it to identify signs of cracking, corrosion, and structural issues.

Flyability Elios 3 Specs / Features:

• Dual Thermal/ 4K Camera Sensor. 12 megapixels HD live streaming

• Lighting. 16k Lumen dust proof lighting with oblique lighting 

• Flight Time. 12 minutes 

• Flight Speed. Up to 7 m/s

• Transmission System. Beyond visual line-of-sight

Learn more about Flyability’s Elios 3.

DJI’s Matrice 300 RTK—External Drone Solutions

The Matrice 300 RTK is a rugged wind turbine inspection drone built to handle extreme weather conditions. Its dynamic range of Zenmuse and third-party sensors are made to support a customized approach for exterior inspections, allowing inspectors to select the right sensor for the work they plan to do. 

Also, the M300’s 55 minutes of flight time means you never have to worry about running out of battery. Integrated safety features like an anti-collision beacon, AirSense, and UAV health management system help keep the drone and—much more importantly—the inspection team safe. 

Learn more about DJI’s Matrice 300 RTK.

DJI Mavic 2 Enterprise Advanced

The Mavic 2 Enterprise Advanced features a small footprint, but despite its compact frame it is a powerful platform for external wind turbine inspections. 

The Mavic 2 Enterprise Advanced’s dual 4K thermal sensor can detect minor defects typically found during a wind inspection, including cracking, delamination, and structural issues. 

Equipping the RTK module is effective for real-time positioning data, creating waypoints as the drone moves throughout a wind turbine. Additional add-ons like the loudspeaker are great for communicating with the ground team throughout the inspection process. 

Learn more about the DJI Mavic 2 Enterprise Advanced.

Skydio X2   

Skydio has built a reputation for its robust autonomous drone technology. The Skydio X2 drone relies on advanced sensing capabilities and AI to deliver precise external wind turbine inspection data.   

The X2’s Superzoom sensor has a 360° view with 100x optical zoom. Being able to detect surface damage from further distances saves time and money. Also, the X2 has six miles of transmission range and precision GPS, allowing it to support intensive commercial operations.

Learn more about the Skydio X2.

Wind Turbine Drone Inspection Cost 

Inspecting a wind turbine requires expensive equipment and highly trained personnel. By choosing to implement a wind turbine inspection drone, companies often realize a 20%-25% reduction on inspection expenses. 

While the costs of drone services vary on different factors, the estimated cost of a wind turbine drone inspection ranges from $300-$500 per turbine.

Wind Turbine Drone Inspection Jobs 

If you are looking for a career as a wind turbine drone inspection pilot, things are looking up. As more wind turbines are constructed, more inspection specialists will be needed. 

According to ZipRecruiter, the national average salary for wind turbine drone inspection jobs is $52,792 annually, with top earners bringing in $104,500.  

Here are some resources to check out if you're looking to start a career in wind turbine inspections:

• Zip Recruiter

• Indeed

• PrecisionHawk

• DroneBase