Each city is outlined by the architecture that inhabits it, especially that which stands imposingly above it and that, with the passage of years and glances, weaves together with its citizens a common history. A common memory. It is difficult to imagine Paris without its Eiffel Tower, as it is to think of Cádiz without the electrical towers in the bay. Two elements that preside over the bustling ecosystem of its port and that, due to their construction and height, are an icon of 20th century engineering.
They are, in fact, some of the tallest electrical towers in the world, but this record is not due to any whim. In the mid-1950s the time came to evacuate the energy from the Cádiz Thermal Power Plant to the peninsula with the idea of ??distributing it throughout the province. “It was decided to place two towers with a height of 150 meters and a sufficient clearance so that ships could pass underneath,” says José Antonio Corbacho, High Voltage Lines technician at Endesa.
The two towers are separated by just over a kilometer and a half, supporting two 132 kilovolt power lines that supply energy to the entire Andalusian city and which has earned them their beautiful nickname: the ‘Towers of Light’. An engineering work in the hands of engineers Alberto Toscano and Remo Scalla, who had to devise a reinforced concrete mooring system that could withstand the pulling of the cables and bridge the Puntales Strait.
The idea of ??facing such a challenge was something that made the project even more attractive. “The difficulties, obstacles and feats of each project are part of the genetic code of engineers and my father was in love with his work,” explains Scalla’s son, Alberto, who remembers how his father spoke to him about the challenges that the projects hid. soft and sandy soils of the bay of Cádiz. And it was not the only thing: “Once the altitude began to rise, strong winds were added.”
At that time, 1961, Corbacho was not born, but the towers do not keep any secrets for him. When he joined Endesa it was 1987 and his colleagues called him “the boy.” 36 years have passed, always near high tension lines. Corbacho fondly remembers those first years in which work, surely conditioned by technical advances, forced him to climb here and there. “It was a more physical job, and a very nice one, which is missed.”
Today he focuses more on administration and supervision, although he also treads ground, reviewing works. Longing, perhaps, for those years when you spent more time with your feet in the sky than on the ground. “It is a unique experience. When you have been working at heights for a long time, you practically work more comfortably up there than on the ground,” Corbacho recalls.
The High Voltage Lines technician at Endesa is not the only member of his family who feels at home being in the heights. His father, who joined the company in 1967, worked there for more than 30 years. And his son does it at AMETEL, a company that, precisely, has been in charge of replacing 14,928 meters of high-voltage wiring. “He’s been up there too, up on the cables,” he shares.
“The towers are a symbol, first of all, for the city. Every time you enter Cádiz, what you find are these magnificent towers. And it is also for the company,” summarizes Corbacho. An idea that Alberto Scalla insists on regarding the work of his father: “When we look at the towers of Cádiz we look at a work of art. What differentiates it from other similar works is its form and function.” And he clarifies: “The ‘ladies’ of the Bay of Cádiz will work for many more decades.”
A luck for all those who, like a lighthouse, search the horizon for its characteristic helical profile, as Scalla remembers: “One day I asked a fisherman what he thought of my father’s towers. He told me that every night when he went out fishing they guided his return.” Relatives from the Spanish Navy based in San Fernando told him the same thing: “After months away from maneuvers, when they saw the lights of the towers, they knew they were coming home.”
That the landscape cannot be understood without the Endesa towers is something that Teófila Martínez, president of the Port Authority of the Bay of Cádiz, knows well. “In addition, they are part of the historical heritage of Andalusia. We Cádiz residents of all generations who know them would not understand the profile of Cádiz without those towers,” she shares. Although Martínez likes to talk more about the profile of the Bay: “It is something very special that has been adding important constructions to its heritage.”
The two towers, Martínez says, have that symbolism that many Cadiz residents like to keep in mind. “They were the first sign that we were and lived on an island, that we needed the help of those two towers to be able to have access to modernity, to the supply of electrical energy,” he values. For a long time they have also been unique witnesses. “The only way to see the transformations of the city from the sky or from a significant height was to climb the towers.”
The towers are inspected and maintained annually. To the routine work we must add that, every 40 years, the wiring must be renewed, since it is considered to have reached the end of its useful life. At the end of 2022 the last renovation of the wiring was carried out. It was divided into two phases: one for each of the circuits. Thus, while the three cables of one circuit were replaced, the other continued working and guaranteeing the electricity supply to Cádiz.
As Endesa explains, these works require lowering the old cable 15 meters above the sea. This action requires an enormous coordination effort that lasts about 8 hours and requires cutting off maritime traffic in the bay. Security has been, in fact, the factor that has structured this project.
“We have not had any incidents or accidents. The safety of people has been prioritized above all, as well as the safety of materials and the structure, but above all of people,” emphasizes Corbacho. The old wiring will serve as a study for engineering universities, where these towers are more than just a case study.