Inside the demodulation basin of the Sant’Antonio sul Talvera hydroelectric plant, the aesthetic involvement is as intense as it is unexpected. It is an artificial reservoir created inside the Monte Tondo which overlooks Bolzano. It collects the water used by the turbines to generate energy and gradually reintroduces it into the Talvera River. The artificial lake is dug into the porphyritic rock and is illuminated by coloured lights and a system of mirrors that generate chromatic reflections. Here waves of color alternate on the surface of the water varying hue and intensity: they appear and disappear in the darkness of the cave with an almost hypnotizing rhythm.
This series tells of a cutting-edge place of energy production from renewables sources and how a community and its territory benefit from this fascinating environmental safety device.
Caves of energy
In the belly of a mountain one discovers the unexpected beauty of a breathtaking panorama which distracts from the original function of the basin, that is to say of being an intermediate station where the water decelerates its violent flow to flow gently into its receptor avoiding peaks in its flow. An environmental safety device wrapped in a cocoon of coloured light, created to improve the production efficiency of a cutting-edge hydroelectric plant and mitigate the damage associated with hydropeaking.
In the hydroelectric lexicon, this term defines the practice of releasing pulses of water to increase energy production and meet peak daily electricity demand. But it can cause damage that affects different aspects. The discontinuous water flows alter the morphology of the river channel, move the sediments of the river bed, damage aquatic life because they destroy the incubation areas of the fauna by dispersing the fish eggs. Thanks to the basin, on the other hand, even the human activities that swarm on the banks of the Talvera become safer, since the underground lake graduates the return flow of the water, avoiding sudden floods.
The new Sant’Antonio power plant, fed by the Talvera river, went into operation in May 2019 and replaced the old one, dating back to 1951, which had a much lower production. It is an innovative and pioneering project under several aspects. Access to the plant is unique in Europe because it is entirely built in a tunnel in the heart of the “Monte Tondo” mountain in Bolzano.
For the first time in the world, a large underground tank with a capacity of 99,000 m³ was built as a compensation basin to reduce the hydropeaking effect of the receiver, the Talvera stream, and therefore significantly improve the quality of aquatic ecology and the safety of the river course for recreational uses. A total of 1.8 km of tunnels were excavated, of which over 500 meters in “free fall”. The water thus arrives from a dam in Val Sarentino with a flow rate of 18 m2/s to the three underground turbines which have a total power of 90 Mw.
Who visits this place reach a hydroelectric plant but discover to be part of an installation, an aesthetic environment made of darkness, light and iridescent colours specially designed to interrogate the human soul and its relationship with the waterfall. The basin is divided into three differently lit caverns. The humidity generated by the waterfalls that fill the reservoirs soars into the air to shimmer in color. It almost seems that the light is tactile, one gets the impression of being able to touch the luminous color with the hands.
Today the artificial lake is a bright, aesthetic and fascinating theatre, but at the beginning of the works it was instead a tiring and hostile environment like that of a mine. After all, the dozens of tunnels and underground caves that structure it, as well as the tanks themselves capable of holding up to 100,000 cubic meters of water, were obtained through excavations and controlled explosions. The lights and mirrors that dot the walls of the rock, in fact, were tailor-made to resist the most difficult conditions of dirt and corrosiveness, and to withstand an operating environment with humidity over 95%. Inside the caves, the luminous and chromatic intermittence that paints the surface of the water induces the viewer to an intimate and chromo-therapeutic, almost gestational dimension, and transforms the caves into metaphorical temples of recovery or rebirth.
«I worked in gas masks and mud up to my knees. When I started, the caves and tunnels were still full of debris and the air was unbreathable. In those conditions it is exhausting to travel even a single meter. It was a very tiring job, which also put my body to the test». It is the voice of Herward Dunkel, the creator of the lighting design implemented in the plant and creator of a phantasmagoria of lights and colours that reconfigures the nature of an industrial space in a permanent art installation.
«I was surrounded by darkness, water and mud. I heard the noises of cars and construction coming from outside faint and muffled, while inside my every breath, word or hammering sound echoed in the artificial gorges. I had muffled and confused perception of sounds. It felt like going back to my mother’s womb» says the South Tyrolean designer who with this project wins, among others, the German Design Award in 2021.
The metaphorical sense of Dunkel’s installation is not resolved solely in the caves filled with water but also invests the territory in which the work is located. «The main function of the basin is to safeguard the mountain environment. The underground lake avoids floods and fish shock, and makes the river bed safer. It is an opportunity for rebirth and healing not only for those inside, but also for the mountain itself and for everything around it».
