Six questions about wind energy (and six answers)
Wind energy is a hot topic. Turbines are popping out of the ground like mushrooms, on land and at sea – or that's how it seems. And if Flanders wants to achieve the climate objectives for 2020, then hundreds more windmills will be needed in the next few years. Eoly, our sustainable energy specialist, also has quite a few projects planned. a lot of people still have questions about them. If you are one of them, scroll through the most frequently asked questions and the corresponding answers.
1. Why are wind turbines good for the climate?
There are lots of answers to this question:
- No use of fossil fuels.
- No emissions of harmful materials like CO2 and fine dust.
- No consumption of water.
- A lot of electricity can be generated from a small surface area.
- There is plenty of room around the turbine for agriculture, recreation and nature.
- Almost everything on a turbine can be recycled.
- And … there is an inexhaustible supply of wind.
2. What about the noise and the shadow flicker?
The government has strict rules that govern the permits for and erection of wind turbines. Our engineers carry out extensive surveys and risk measurements before we do anything else. If the results aren't positive, then no turbine is put up. We also pay particular attention to the noise and the shadow flicker.
Yes, a wind turbine makes a noise. How loud it seems to you depends on the wind speed, where you are standing and the ambient noise. The government imposes noise standards for each turbine. So, before we even position one, our engineers carry out extensive noise simulations and calculations. And we take regular measurements to check that our turbine isn't exceeding the current standards.
If the sun is low in the sky and shines through the turbine rotor blades at a specific angle, this causes shadow flicker. The laws about this are stringent: in Flanders, you must not suffer from this phenomenon for more than eight hours over a one-year period, and never for more than 30 minutes per day. To counteract shadow flicker, we sometimes stop our turbines on a temporary basis. And the rotor blades have a special, anti-reflective layer.
3. How much energy does a wind turbine supply?
That depends on several factors:
- The height of the turbine: the taller the mast, the more electricity it produces. A turbine measuring 180 m, for example, supplies twice as much energy as one measuring 120 m.
- The length of the rotor blades: the longer they are, the higher the yield.
- The location of a turbine: in some regions, the wind blows more often or more strongly.
- And, of course, … the amount of wind. So, each turbine has a slightly different yield. On average, one turbine can supply 1,800 families with electricity.
4. How long does a wind turbine last?
Current turbines will deliver green energy for a good 20 years. And modern ones are easy to recycle at the end of their service life. The metal is reused and the fibreglass from the rotor blades is also repurposed; for example, as post boxes, or as the filler in adhesive and cement.
Our oldest turbine, the V66, was dismantled after 18 years. The top section of the mast, the gondola, the rotor and the blades were reused in an education centre. The rest was recycled. So, no waste.
5. Are wind turbines harmful for birds, bats and fish?
When we select a location for a new wind park, our engineers also look at local flora and fauna. Are there lots of birds or bats in the area? What is the potential impact on nature? What information do we have about the area? All these questions are decisive for approval.
But one thing is sure: animals are extremely resourceful in how they handle wind turbines, both on land and at sea. In Germany, some turbines support nesting boxes for peregrine falcons. The offshore wind parks in the North Sea are also a popular resting place for birds, fish and seals. Very few boats travel between the wind parks and fishermen are not allowed to use drag nets. We are even trialling a project to cultivate mussels. In other words, all good news for life under the sea.
6. What does a wind turbine look like on the inside?
Have you ever climbed inside a wind turbine? If the answer is yes, then you are lucky. Because safety reasons mean that only specially trained technicians and engineers are allowed to access the machine room. So, we have made a 360° video clip that lets you explore all the nooks and crannies of a turbine.Watch the video clip
With this initiative, we contribute to the following Sustainable Development Goals of the United Nations.