The story of how we came to control the wind

Conquering the elements in the service of progress

The story of the human race is a fight to manage the elements and make them serve civilization. Tradition and mythology are full of brave people who challenged nature, sometimes with luck and sometimes without, allowing humanity to make an evolutionary leap forward. Prometheus brought fire under control, Daedalus managed to conquer the wind and rose like a bird to escape Crete, Alexander tackled the power of the sea and created the first device with which man could dive…

Humans have always advanced by non-conforming. And it is this narrative by which we can explain wind power. Wind turbine generators, colossal machines able to befriend the wind to supply us with clean energy, have their origin in the windmills of Persia, 1,000 years before Christ. Between these first devices that flirted with the wind to grind cereals, and the modern turbines of today, there have been centuries of research and progress.

In its 25-year history of developing wind power, ACCIONA has installed over 230 wind farms for itself and third parties, comprising over 6,400 wind turbines. Its facilities alone generate clean energy equivalent to the demand from more than five million homes in 14 countries on five continents. It’s been an adventure that has needed patience, trust and self-belief. Today, we at ACCIONA are able to tell this great story… of how we came to control the wind.

El Perdón wind farm, a living wind power memory

They appeared colossal in December 1994. Six wind turbine generators installed that year in the El Perdón hills near Pamplona, in the Navarre region of Spain. Their hubs, the turbine´s “nose”, rise 40 meters above the ground, the blades reaching a vertical height of 60 meters. If we were to stand on the pedestal of the Statue of Liberty and look up, it would be like looking up from the ground at one of these turbines. Twenty-five years have passed and El Perdón continues to operate impassively as it did on its first day of operation, even though it was only meant to have a lifetime of 20 years.

El Perdón and El Cabrito wind farm (formerly kW Tarifa) are the oldest commercial wind farm in Spain, both commissioned by ACCIONA. 1994 was a milestone in the clean energy calendar and the first step in transforming winds into non-polluting electricity. These machines of 500 kW nominal capacity represented the start of the deployment of clean energy in Spain.

Two years later and El Perdón had welcomed another 34 turbines to take its total capacity up to 20 MW, which it continues able to generate today. The facility owes its pious name to the surrounding mountain range, through which the famous Santiago Way meanders. Its giant machines have also paved a way of their own… by which wind power has become a tangible reality right across the world. El Perdón became a technological, socioeconomic and environmental benchmark for the energy sector, leading European rankings in productivity, and is now a part of the history of wind power in Spain.

The oldest wind farm in Cádiz

Our walk through the history of how we harnessed the winds takes us to Cadiz in 1995, the year in which the El Cabrito wind farm was inaugurated, the oldest in the province. Despite the number of years the installation has been standing, it looks just as new today as it did at the end of the last century. El Cabrito has been refurbished 24 years after it was commissioned in order to improve its technical efficiency and reduce the impact on the local environment.

The 90 turbines with 330 kW of unit capacity have been replaced by 12 units of Nordex-Acciona Windpower technology turbines, 8 of 3 MW and 4 of 1.5 MW. The numbers speak for themselves. Not only has having fewer turbines not reduced total capacity, but production has increased by 16 % due to the increased efficiency of the new units.

The effects of fewer turbines are observable in the surrounding landscape, since about 24,000 m² of land has been recovered. The project involved removing 3.4 kilometres of access roads, as well as platforms and other infrastructure, all of which are no longer needed in the new wind farm.

El Cabrito now looks like a vast area of sustainable land where nature and renewable energies coexist in the greatest possible harmony. Anyone approaching this wind farm in Cadiz will be able to detect the aesthetic and acoustic improvements brought about by these changes.

Above all, it’s the birds that nest in the area that are benefiting from the upgrade. The distance between turbines, which was previously between around 45 and 65 metres, has now increased to between 170 and 300 metres, making it easier for birds to fly between them. In addition, the slower rotation speed of the blades reduces the risk of birds being hit by them.

Experimenting with the wind

ACCIONA has installed over 220 own wind farms and another 60 for other developers, comprising around 8,000 wind turbine generators in total. Of these facilities, six are experimental areas in which new models are tested.

The Vedadillo Experimental Wind Farm, also located in Navarre, the home of wind energy exploitation, is one of the most advanced. Here, the turbines are submitted to artificial vibration testing for fatigue, simulating the passing of years and checking their resistance to extreme temperatures.

Vedadillo wind farm is home to three AW 3000 wind turbine generators of 3 MW nominal capacity, one of the most successful models on the current international wind power market. The units installed at Vedadillo have a hub height of 120 meters and rotor diameters of up to 125 meters, with one of the biggest swept areas in the onshore wind energy market. Now, not even the Statue of Liberty, pedestal and all, measures up to such a titan. End to end, its blades are longer than the length of a top football pitch and, when moving, its circumference covers more ground than the playing area as a whole.

The video, shot with 360° technology, gives a feeling of the sheer size of these powerful Anemoi (wind gods) when standing beside, or inside, them

The productive capacity of these turbines is six times greater than that of its counterparts at El Perdón. Each AW 3000 machine can supply the demand from 2,000 homes, avoiding the emission of more than 7,000 metric tons of CO₂ from coal-fired power stations. Their ability to exploit the wind is becoming ever greater, too, as in a marriage where over time one partner gets to know the other better. The turbine generators begin to produce electricity and reach their maximum potential at lower wind speeds and, as such, can accomplish more hours of generation per year than before and at facilities with fewer turbines.

In the 25 years that have passed since that first wind farm in Navarre was commissioned, the efficiency of these machines and the capacity to generate clean energy for our homes has not ceased to grow. The capacity of wind turbines has increased by six times and production eightfold. The towers are three times higher and the diameter of the rotor has tripled. And these figures are small compared to the latest models to launch on the market, which ACCIONA is incorporating in its most recent facilities.

Wind energy continues to be the most efficient source of clean energy: inexhaustible, renewable, reducing energy imports, generating local wealth and employment, and contributing to sustainable development.