Wind Energy

One promising source is wind energy which Luxembourg is seeking to expand significantly in the coming years. We are all familiar with the sight of tall, white wind turbines, but you might not know how they work. Keep reading to find out more.

It might seem counter-intuitive, but wind energy is considered to be a form of solar energy. This is because wind is caused by a combination of the earth's rotation and the sun heating up the surface of the earth unevenly.

For instance, during the day, the air above water doesn't heat up as quickly as the air above land. In very simple terms, the warmer 'land' air then rises and is replaced by the colder 'water' air and the changes in pressure 'create' wind. This wind can then be used to generate energy with the help of wind turbines.

The idea of using wind energy is far from new, and people used it way before the invention of electricity. In ancient Egypt, wind-energy was used to put boats in motion with sails and windmills were already grinding grain and pumping water in Persia.

But it took until the 12^th century for windmills to be used in Europe. After the discovery of electricity in the 18^th century, wind energy started to be used to produce electricity in the late 19^th century.

James Blyth, a Scottish engineer at Anderson's College (now the University of Strathclyde), was the first to invent a turbine that could generate electricity from wind in 1887. Blythe stored the electricity generated by his cloth-sailed wind turbine in accumulators (a device used to store and release energy as needed).

Blyth intended to offer the electricity to a neighbouring village, but its inhabitants were suspicious of this form of energy and declined his offer. Finally, an improved version of Blyth’s invention came to good use at Montrose Lunatic Asylum, where it successfully generated electricity for 30 years.

Despite this early success of wind energy for public use, the technology wasn't more widely used in Britain until 1951.

Following Blythe's efforts, Poul la Cour laid the foundations for our modern wind turbines in Denmark in the late 19^th and early 20^th centuries. La Cour was particularly concerned with the storage of excess energy for days when there was less wind and he started to experiment with this in the Danish village of Askov.

Unwilling to rely on accumulators for energy storage, la Cour experimented with electrolysis (splitting water into oxygen and hydrogen with the help of electricity). When this proved to be unreliable, he invented the Kratostate, a device which steadied the rotation of the blades even on low wind days.

Modern wind turbines now effectively transform the kinetic energy of the wind (caused by its motion) into electrical energy. The rotor, usually composed of 3 blades, captures the wind and transforms its kinetic energy first into mechanical energy, which a generator then transforms into electrical energy.

With the help of underground cables, the electricity is moved to a transformer substation, from where it is then distributed to be used in houses, schools, or wherever else it is needed.

A typical wind turbine is between 80 and 120 meters tall, and there are 2 main types, namely horizontal or vertical-axis turbines. The former is what most people are familiar with; here, the blades have to face the wind in order to operate properly.

In the case of the latter, the direction of the wind doesn't matter because the turbines are what is known as 'omnidirectional', meaning they can 'receive' wind from all directions without having to be adjusted. In addition, they also work well with lower wind speeds.

The 2 major types of wind energy are onshore and offshore wind energy. As the name indicates, onshore wind energy designates the electricity that is generated from wind turbines that are installed on the land, whereas offshore wind energy is electricity generated by turbines installed in the high sea.

Offshore wind energy has the benefit that the wind supply is more constant and also stronger and can thus generate more electricity.

Using wind power has many benefits; it is a clean form of energy, and thus doesn't harm the environment, unlike fossil fuels; wind is also a cheap and unlimited resource, making it the ideal candidate for sustainable energy production; and with continuing technological improvements, the turbines will become more efficient and will steadily produce more electricity.

Luxembourg currently has 62 wind turbines, with new wind farms currently under construction in Dalheim, Arentztal, and Sudwand. On this website, you can see how much energy some of the already existing wind farms generate and how many households they supply electricity to across a year.