Are today's standard lubrication tests enough to ensure the long-term performance of wind turbines operating in extreme environments?
In a unique collaboration between industry and research, Shell Lubricants and the Fraunhofer Institute for Wind Energy Systems (IWES) are challenging assumptions about how wind turbine greases perform under actual operating conditions. Their joint investigation dives into the nuances of grease degradation, moisture tolerance, and compatibility—factors critical to turbine uptime and reliability.
This partnership moves beyond controlled lab settings to recreate real-world stress scenarios, allowing a deeper understanding of how greases age, protect, and fail. The findings not only guide lubricant selection for turbine operators but also signal the need for new industry standards.
To simulate the harsh environments wind turbines face—from offshore humidity to Arctic temperatures—researchers condensed a full year of operational stress into a 14-hour test cycle. This model helped expose how greases handle oscillating loads, low-speed movement, and water ingress—factors that traditional high-frequency lab tests often fail to replicate.
Fraunhofer IWES’s full-scale bearing test stands (up to 6 meters in diameter) enabled the team to simulate real pitch system dynamics, providing actionable insights on how greases perform at speeds and loads actually experienced in the field.
One of the most eye-opening results was the variability in water tolerance. Some greases failed with as little as 3% water contamination, while others—such as Shell Rhodina BBZ—remained structurally stable with up to 10% moisture. For offshore turbines exposed to persistent condensation and spray, that kind of resilience isn’t a nice-to-have; it’s essential.
Another key result came from extended testing. Greases like Shell Rhodina BBZ and Shell Gadus S5 V110KP 1 not only maintained flow properties in wet and dry conditions but even helped redistribute wear particles—reducing fretting and maintaining surface integrity after hundreds of hours of use.
Switching greases in large turbine systems is no small task. Because completely flushing old lubricant is nearly impossible, Shell and Fraunhofer also tested grease interoperability. Their results showed that Shell’s products demonstrated no significant degradation when mixed incrementally with existing greases—helping operators transition more smoothly without extended downtime.
With turbines now deployed in everything from tropical humidity to Arctic chill, grease selection must account for extreme cold and fluctuating loads. Tests down to -30°C revealed that only a few formulations—like Shell Gadus S5 V110KP 1—retained pumpability and lubrication capacity in sub-zero conditions, making them ideal for northern European and North American wind fleets.
As predictive maintenance and sensor-based systems become standard, Shell and Fraunhofer’s work also lays the foundation for smarter, on-demand lubrication strategies. Instead of relying on fixed schedules, operators can reduce waste and extend component life by applying grease based on load, vibration, or temperature data in real time.
This study marks a major step forward in aligning testing procedures with operational realities. As the wind industry pushes for more reliable, long-lived turbine fleets, there is a growing call for standardized lubrication performance metrics rooted in real-world dynamics—not just lab benchmarks.
Future advancements could include custom grease formulations with enhanced base oils and novel additives tailored for wind applications. But even now, with tools like those developed in this collaboration, turbine operators are better equipped to reduce maintenance frequency, improve system resilience, and lower total lifecycle costs.
Shell and Fraunhofer’s research underscores that the key to wind turbine reliability may be as fundamental as the grease that keeps the blades turning.
🔗 Learn more: