Wind power is an excellent source of sustainable power. Wind energy never runs out. Moreover, it’s always a clean energy source, unlike the conventional fossil fuels, like coal or oil. The demand for fossil fuels worldwide is immense, the majority of the developed countries depend on oil and gas supplies. This dependency on fossil fuels can sometimes lead to dramatic consequences. The most recent case of such negative consequences happened in 2009 during the Russia-Ukraine conflict. As a result of this conflict some parts of Eastern Europe were cut out from the gas supplies.
Moreover, natural reserves of fossil fuels are rapidly running out. To ensure that we have enough energy to satisfy our needs, we need to learn how to efficiently use the renewable energy sources. Wind is one of such sources and wind power technologies are currently developing at an increasing pace.
Another important disadvantage of conventional energy sources is the continuous release of greenhouses gases (especially CO2) into the atmosphere. These greenhouse gases contribute to Earth’s climate change, influencing all aspects of life on the planet. Wind power does not have this disadvantage.
Using wind turbines is the most common way of generating sustainable wind energy. There are two types of wind turbines:
- Wind turbines rotating around a vertical axis;
- Wind turbines rotating around a horizontal axis.
Due to the fact that wind turbines with a horizontal axis are much more popular, we will focus on them here. Wind turbines are often organized in the so-called wind farms. Such farms usually consist of hundreds of turbines, either on land or off-shore. A big advantage of off-shore wind farms is that they do not interfere with the day-to-day business of the society. Moreover, winds are often stronger at sea. The biggest disadvantage is that such farms require expensive long high voltage cables to transfer the electricity to land, where we need it.
Principle of operation
Any wind turbine consists of three main components – the blades, the nacelle with the generator inside, and the tower. The blades are always directed towards the wind. Modern wind turbines have the ability to change the position of the blades, so that they are always at an optimum angle. The lifting force, caused by the flow of moving air, rotates the blades of the wind turbine.
The nacelle is the part of the wind turbine on ttop of the tower. The blades are also attached to it. The nacelle combines the basic operational parts of the wind turbine, such as the shaft (the axis) and the generator. The rotating blades cause the shaft to rotate as well. Special gear wheels transfer this rotational energy of the shaft to the generator. The generator then generates the power – that’s the wind power!
A generator of a wind turbine actually works just like a big dynamo. The movement of the shaft in a magnetic field creates the electric currents. The nacelle contains another important element of a turbine – a transformer. The transformer creates a potential difference (voltage), so that the generated current can be efficiently transferred.
The heights of the towers of wind turbines can vary significantly. The exact height depends on the specific wind conditions in the region.