La Bianzone hydroelectric power plant, located in Colòra, represents a significant piece of the town's history. Its story is narrated in a 1969 document written by Aldo Gadaldi, whose family were custodians of the power plant for decades.
Birth of a Revolutionary Project (1913-1914)
In 1913, a group of willing citizens from Bianzone and Villa di Tirano formed a joint stock company and decided to bring electricity into their homes, abandoning the obsolete oil lamps. At a time when only Sondrio and Tirano had electricity in Valtellina and the local economy was in difficulty, the idea of harnessing the power of the Valle torrent to produce energy was revolutionary.
The initial project, entrusted to the’engineer Italo Bongioni, envisaged taking water from the Bianzone and Boalzo streams and conveying it to a power station to be erected at Galeazza (alla Gatta). However, opposition from the population, fearful for the operation of the mills and sceptical about electricity, led to an alternative plan.
An alternative project and construction
They opted for one damming of the Bianzone stream at Mulin dei Busnat. The water was then conveyed into a settling tank for purification and from there into a 1,000-metre-long concrete canal. This canal carried the water to a loading tank at La Muta, from where a 360-metre steel penstock with a height difference of 250 metres started, which fed the power station's turbines.
The power station was inaugurated on 1 July 1914. Initially, energy consumption was modest: only one electric motor, a few irons and no more than three light bulbs per house.
Development, nationalisation and temporary closure
Until 1930, the power station proved functional, but with the growth of industry and the improvement of the quality of life, its capacity became insufficient. As a result, Teglio, Tresenda and San Giacomo were disconnected from the supply. In 1934 a second generator group 150 horsepower to increase power. In 1947, in the face of a further increase in consumption, an expensive hydrocarbon engine, used only in emergencies.
In 1963, electricity was nationalised and the power plant was incorporated into the’Enel. It operated under this new management until 23 May 1969, when it was finally closed down. Aldo Gadaldi concludes his report with deep regret for the plant's closure.
The rebirth of the control unit
Fortunately, Aldo's pessimistic predictions did not entirely come true. Since the end of 2011, the control unit has returned to full operation, thanks to a major investment by the municipality of Bianzone. It now exploits two penstocks, also using water from the municipal aqueduct, continuing to generate energy for the community.
