Wind energy in general is becoming a substantial part of the energy mix in many countries. Most of the operational wind turbines worldwide have been placed onshore, at sites which can be accessed quite easily for maintenance tasks.
In many of these area’s the environmental loads are not that extreme. As the wind turbine industry is rapidly expanding, an increasing number of wind turbines are now being installed remotely were the wind resources are good and conflicting interests (like opposition by nearby residents – not in my back yard syndrome) are few. Examples of remote located onshore wind turbines are those installed for example at mountains, in the desert, at so called cold climate locations, or even in extreme environments like the arctic.
Also offshore wind turbines can also be classified as remotely located as more and more of these planned turbines are installed far at sea up to 100 km from shore. In some of these remote areas, wind turbines need to work under extreme harsh conditions and additional uncertainties are involved in terms of operations and maintenance (O&M) compared to standard turbines. Locations like for example Inner Mongolia, Canada, the Scandinavian countries and Russia the ambient air temperatures can drop to -40°C to -45°C. In arctic regions even extreme temperatures of -55°C to -60°C occur during winter time. On the other hand, wind turbines located in hot regions (i.e. deserts in India, Afrika, China,…) can suffer from extreme heat with temperatures up to +58°C maximum.
There is the apparent need to understand and mitigate the additional risks. High reliability for every component is key for these machines which are installed in remote locations in order to avoid expensive maintenance tasks.
Before reliability become an issue, all components need to be tested to see what the behaviour and performance characteristics are at extreme temperatures. An example are the service cage tower hoists. These are ladder- or pretensioned wire rope guided access & service cages for maintenance, inspection and repair purposes inside wind turbines and other tower applications.
Sky Man International, a Belgium company with 20 years of experience in the suspended powered access business, is very active on the market of service cage wind turbine tower hoists. The Sky Man hoists use a state of the art hoist principle, based on a polymer compound pressure ring. Although this makes it a very steel wire rope friendly design, the performance of this concept at extreme temperatures needs to be validated.
The OWI-Lab is an open and independent testing facility and is there to accommodate this kind of testing. The climatic chamber with 8m of height and temperature ability ranging from -60°C to +60°C, ensures that all required temperatures can be reached with a special hoist test setup inside. After the desired testing temperature is reached, the performance can be thoroughly tested and monitored. In this way Sky Man International gains a lot of knowledge of the systems behaviour at extreme temperatures and can guarantee stable and safe performance at these temperatures and more reliable behaviour on long terms.
[mappress]
Press release, March 11, 2013; Image: owi-lab