Frequently asked questions about wind energy

What are the benefits of wind energy?

Wind turbines have many advantages. Wind energy is 100% clean energy that is free from all political, ethical, economic and environmentally damaging problems inherent in coal, oil, gas or nuclear power. Wind energy has none of the major drawbacks inherent in other forms of electricity: no geopolitical risks, no foreign energy dependence, no fuel risk, no exploration, no refineries, no pipelines, no depletion of raw materials and no radioactive waste and virtually no carbon emissions.

There are also benefits for the inhabitants of the municipalities concerned: they can (from one share of 125 euros / family) invest in wind turbines and share in the profits they generate.

What are the disadvantages of wind energy?

Like any form of energy generation, wind energy has some disadvantages.

The amount of electricity generated by wind turbines is not constant, and depends on the wind speed.

Wind turbines have an impact on the landscape: they are visible from afar. They also make noise (mainly caused by the aerodynamic swishing of the blades), and they can cast shadows (the shadow created when the sun shines through the rotating blades of the wind turbine). Wind turbines can also have an impact on birds and bats in the area.

All potential impact on humans and nature for a wind farm is examined in detail in the environmental impact being made in the context of license applications.

How much power does a wind turbine produce?

One wind turbine in Flanders produces between 12.000 and16.000 MWh depending on, among other things, the wind speed at the site, the size and type. This is enough to meet the annual electricity consumption of 3,500 to 4,500 families.

Does wind energy receive many subsidies?

Almost all forms of energy are subsidized, including wind energy.

For traditional forms of electricity generation, there are externalitiesthat are not borne by producers but by society, and should therefore be considered as a subsidy. This concerns, for example, medical expenses borne by social security but caused by air pollution from coal power stations; provisions for costs of nuclear accidents due to the lack of insurance of the operators of nuclear power plants and costs as a result of climate change.

In addition, there are direct subsidies for traditional forms of energy production. In the past, this usually concerned subsidies for (government-built) nuclear power plants. Nowadays this usually concerns subsidies for end users of electricity from (mostly) polluting sources.

Wind farms in Belgium have a support (subsidy) of around €9.25/ MWh. This is far less than, for example, the subsidies needed for a new generation nuclear reactor.

Isn’t it better to place all wind turbines in the sea? There is more wind and no one is bothered by it.

Wind turbines at sea is a good idea: there isn’t just more wind, the wind is also more constant and predictable than on land. Wind turbines at sea, however, have disadvantages. The main disadvantage is cost: because of the complex grid connections, and deep underwater foundations, the power generated by wind turbines at sea is a lot more expensive than power produced by wind turbines on land.

Therefore, wind turbines at sea need more funding than onshore wind turbines.

Do wind turbines use rare earth metals, such as neodymium?

Rare earth metals (including neodymium) are used in many common electronic home, garden and kitchen appliances: laptops, mobile phones, stereos, tablets…

Most mines where rare earths are extracted are located in China. The extraction of rare earth metals is, in many cases, accompanied by large-scale environmental pollution.

Rare earths are used in certain, mainly Asian, types of wind turbines with a permanent magnet generator. None of the wind turbine manufacturers that are eligible for the delivery of wind turbines for Storm wind farms use permanent magnet generators based on rare earth metals. Most of the other wind turbines in Flanders also do not use permanent magnet generators on the basis of such metals.

How much noise does a wind turbine make?

The noise of a wind turbine is mainly caused by the aerodynamic swishing of the blades.

The noise of wind turbines in homes is limited by the government: the legal night-time noise level near to homes is 39 dB (A) in residential areas and 43 dB (A) in agricultural areas.

There are various comparative tables available on the Internet that give you an idea about what these noise levels mean exactly.

What is the effect of wind turbines on the bird population in the vicinity of the wind farm?

Wind turbines may indeed have an effect on birds: some birds adapt their behaviour to the presence of wind turbines; others do not. In both cases, adverse effects may occur on the bird population. Therefore, it is important that food, rest and breeding places for birds are mapped in detail before wind turbines are built. The same applies to the migration routes.

These elements are mapped in detail as part of the environmental impact report.

Can bats in the area be affected?

Wind turbines can have an effect on bats.

It is therefore important that the routes followed by bats are mapped in detail before any wind turbines are built.

These routes are mapped in the context of the environmental impact report.

What is shadow flicker exactly?

Shadow flicker is the shadow created when the sun shines through the rotating blades of a wind turbine.

If such a shadow falls on a house, it is very annoying inside it: the effect of the flickering on-off shadow created in a house because of the shadow of the blades falling on the windows is called shadow flicker.

Shadow flicker is an annoying side effect of wind turbines, which is regulated very strictly: there should never be more than 8 hours of shadow flicker per year on homes in Belgium.

Wind turbines must be equipped with a shadow flicker detector with a stopping device, which automatically shuts down the wind turbine when there are more than 8 hours of shadow flicker per year in a particular home.

How does the shadow flicker detection system stop the turbine exactly?

The wind turbines are equipped with a light sensor. The location of all the homes in the area is programmed in the software that controls the wind turbine. This software always knows the position of the sun, the position of the blades, the location of the homes, and knows on the basis of the light sensor if it is cloudy or not.

On the basis of all this information, the wind turbine therefore knows whether there is shadow casting in a certain property. This is recorded in a logbook for the purpose of the environmental inspection. As soon as the legal standard has been achieved for a given property (8h per year), the wind turbine stops just before the shadow of the blades reach this property. The turbine makes the reverse movement as soon as the sun is higher in the sky and the shadow has moved over the house. The loss of production for a wind farm under this downtime is estimated at 1 to 2% per year.

Are wind farms financially viable?

Definitely. There are no public examples to our knowledge of wind farms in Belgium that are unprofitable or have ever encountered financial problems.

Despite the profitability of most Belgian wind farms, it is of course never ruled out that the owner of one or more wind farms may have financial problems. This has already happened, but it does not affect the profitability of wind farms in Belgium.

Are wind turbines safe?

Accidents involving wind turbines are rare. The Flemish government also stipulates a number of safe distances from buildings, infrastructure and housing. For a standard turbine, the government requires that external infrastructures (roads, canals, etc.) are at least 50 metres away from the tower. To avoid disruptive effects on nearby residents, turbines are preferably built at a distance of 250 metres from housing.

Can wind turbines be built anywhere in Belgium?

Unfortunately not. First and foremost, it is important that there is sufficient wind at the implantation site. This depends on the local topography, terrain, the distance to the sea and the presence of high obstacles. In addition, the provisions on land-use planning must be respected. It must also satisfy a number of conditions relating to, among others, safety, birds, and distance to natural areas.

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