Situated on a remote island at the far tip of Norway, Havøygavlen is the world’s most northerly wind farm.
Deep in the Arctic Circle, the weather here is both unpredictable and extreme. Temperatures can drop to -25°C and winds can howl at over 180km/h.
So why build a wind farm in such a hostile location? The Arctic offers massive potential to generate clean, renewable energy due to the high average wind speed (around 30km/h) and the fact that colder air is denser, meaning it carries more kinetic energy.
Designing a wind farm to handle these conditions is challenging. The wind and cold make the turbines wear faster than in other locations.
When the wind is from the south, it comes in a smooth stream, perfect for large-scale wind turbines. But when it’s from the north, it rises up the cliff face from all directions in a very turbulent stream that can present negative wind shear and other problematic wind phenomena. This turbulent wind places extraordinary loads on the pitch and yaw mechanisms that are used to adjust the blades and keep the turbines facing into the wind to capture the most energy.
For the bearings it is necessary to use a lubricant that won’t freeze, and one whose properties remain largely constant over a wide range of temperatures. The cold can also cause icing on the rotor blades, potentially unbalancing rotors and reducing power output of the turbines.
Maintenance is therefore a primary concern for Havøygavlen’s owners, Arctic Wind. Unprepared for such harsh conditions, the wind farm’s early years were hardly a success. The turbines twice had rotor blades sheared clean off, and once a turbine even collapsed to the ground in a storm.
It’s not just the extreme weather that makes life difficult for the Arctic Wind team. Transporting spare parts and maintenance crews to such a remote location is a logistical nightmare, and during the Arctic winter the area is plunged into 24-hour darkness.
The identification and prediction of failure are a key part of wind farm operations. When Fedem Technology approached them with a proposal to try a new technology, the operators at Havøygavlen jumped at the chance.
Fedem (which stands for Finite Element Dynamics in Elastic Mechanisms) is a Norwegian company specialising in advanced engineering analysis. It has developed cutting-edge software for modelling structures and mechanical systems under the influence of complex loads.
The software uses a nonlinear structural dynamics approach to simulate the system’s dynamic behaviour and enable new ways to accurately monitor and calculate the remaining life of the asset. The software detects both instantaneous consequences of one-off events and the long-term effects of cyclic loads.
The principle is to create an advanced digital model of physical objects, and update it with remote sensor feeds.
Analysis is run based on the laws of physics. “We create a digital clone of the installation, collect sensor data from the physical structure in the cloud, analyse the data we get in real time, and always have an overview of the structure’s condition,” explained Arnulf Hagen, CEO, Fedem Technology.
Fedem was recently acquired by SAP. With this acquisition, SAP plans to build an end-to-end #IoT solution in which a digital avatar continuously represents the state of operating assets through feeds from sensors, replacing the need for physical inspection with a “digital inspection.”
“When you observe the same things remotely through the Internet as you would when you observe the object physically, that’s when you start getting real value for money,” says Hagen.
For more on how cutting-edge technology can be used to enable alternative energy sources, see Battery Power From A Bandage?