Hydroeletric plants in Italy: which is the largest?

Renewable energy sources are an important target for Italy too

Electricity should be increasingly produced with renewable energy sources. The objective, during the following years, is to leave all fossil fuels behind, and possibly all polluting thermoelectric plants – replacing them with photovoltaic plants, wind farms, and geo-thermoelectric, biomass plants and hydroelectric plants.

According to the data released on March 29, 2021 by the GSE in the Statistical Report on Energy from Renewable Sources in Italy - related to 2019 - in this country the total gross production from renewable sources has reached almost 40% of the electricity mix. Hydropower is the most used renewable energy source. How many hydroelectric plants are there in Italy, and where are they located? We sometimes have to deal with huge constructions. There are, oftentimes, not cared much about, even by those living just a few kilometres away. Only just recently, people began to do more in this respect, to bring the public and these huge engineering works closer, by organizing exhibitions and guided visits.

Hydroelectric Power in Italy

Hydropower is Italy’s most productive renewable energy sector. Hydropower plants, in fact, produce 41% of the overall generated electric energy here: 46 TWh every year, which amounts to 16.5% of Italy’s total amount of produced electricity. But how many plants are needed to generate this power? There are 4,300 hydroelectric plants in Italy, with over 1500 people working there. In most cases, the existing hydroelectric plants are quite old, as they were built more than 70 years ago. Their capacity to generate energy is endangered by two things: their age and the consequences brought about by climate change. These two factors, jointly, undermine the potential of many of these plants.

The sector’s experts stated that it is fundamentally important to renovate these hydropower plants. In fact, the report entitled "The economic and environmental contribution of hydroelectric power in Italy", written by Althesys, for Utilitalia states that with adequate renewal and maintenance interventions, Italy’s current hydropower sector could actually grow by 6,000 MW by 2030. If we do choose to tread along this path, we could generate an extra 4.4 Twh of renewable source electricity, in just a decade, in an environmentally friendly way, while also eliminating more than 2 million tonnes of CO2.

Italy’ hydroelectric plants

Italy’s landscape, with its numerous mountain chains, offers the perfect location for its many hydropower plants. In 1879, in the United States, the first hydropower station in the world was built at Niagara Falls. Shortly afterwards, in Chiavenna, in Lombardy, Lorenzo Vanossi built the first Italian electric generator to work with water; in 1895, the first real hydropower station was put into operation at Paderno d'Adda, and soon followed by the Vizzola sul Ticino one. If, these plants, in the past, could have been quite rare, today, they are everywhere. They are so numerous that it is very difficult to establish their exact location.

Italy’s largest hydropower plant

Italy's largest hydropower plant is located in Piedmont, in the Province of Cuneo, at Entracque. This very small town, with just over 800 inhabitants, during the high season, has over 5000 people, the majority of which are tourists. They are attracted by the town’s position and the fact that it is located at the very heart of the Maritime Alps. The Luigi Einaudi hydropower plant was, in fact, built in the mountains, during the '70's. Works actually began in 1969, but the plant started to operate only in 1982, due to the delays caused by the area’s difficult weather conditions, which allowed works to be carried for just 6 months, each year.

The Entracque plant uses two different water levels to operate: the Chiotas-Piastra passage one, and the Rovina-Piastra. The Chiotas dam sits almost 2,000 metres above sea level, with a reservoir of 27.3 million m3; the Piastra dam, on the other hand, is located 1,000 metres under the first, with a 9 million m3 water reservoir. The Rovina Lake is located somewhat halfway between these two dams, at 1,500 metres. A long piping network connects the three reservoirs, running underground, until it reaches the heart of the hydropower station, which is entirely excavated inside the rocks.

Bringing all the water to the turbines was not an easy task at all. Works to build the dam, the strengthened pipelines, the diversion tunnels and the power plant, were often interrupted by strong frequent snowfalls, due to the fact that the dam is located at very high altitude. When works were completed, they gave birth to Italy’s largest hydropower plant. Its 1,065 MW generated power can meet the overall needs of the Province of Turin (2282 million people). The Luigi Einaudi hydropower plant is open to the public. Interesting guided visits provide visitors with a three-storey scale model detailing how the plant functions.

Other large Italian hydropower plants

Another large Italian hydropower plant is the one located in Edolo, in the Province of Brescia. Just like the Einaudi plant, this too is owned by Enel. To generate 1,000 MW, it makes use of the energy generated by a water drop of 1,265 metres.

Moving further down, towards Southern Italy, we can find another of Italy’s large hydropower plants: the Domenico Cimarosa one at Presenzano, in the Province of Caserta. With similar generated power to the Edolo plant, it makes use of two water drops, each differing 500 m in height. Most of the Italian hydropower plants are quite small. In fact, approximately 3,000 plants generate 1 MW, while less than 1,000 plants generate between 1 and 10 MW.