How much hydroelectric energy is produced in Italy and where

Hydropower, also referred to as hydroelectric power, is Italy's oldest source of renewable energy, with a history that has its roots in the late 1800s, when the country was the world leader in the development of water systems for generating clean energy. Although solar and wind power are likely to be the two main candidates driving forward Italy's green future, hydropower still accounts for more than a third of the nation's renewable energy. The physical features of Italy, with the Apennines and, in particular, the Alps, provides the necessary steep terrain that makes it possible to build highly productive hydropower plants. So far, Italy's hydropower potential has, for the most part, been exploited well, although not completely. Significantly, however, those power plants that have been built and kept operational are now starting to show their age. A study by Althesys, for example, estimated that if just a third of Italy's hydropower plants were to undergo a technological upgrade, the amount of energy generated each year could be increased by almost 10% by as early as the end of the 2020s. Where we started and where Italy is now A century ago, between the beginning of the 1900s and the end of the First World War, hydropower was the undisputed star in Italy's energy transition from fossil fuels toward renewable energy sources. As soon as technological innovations at the end of the 1800s made it possible to transfer energy from one place to another, the huge hydroelectric potential of the northern part of the country was immediately put to use. It was even believed that this source of green energy – the only one in use at the time – could, on its own, be sufficiently abundant to enable Italy to become energy self-sufficient: so much so that it was dubbed the “white coal” of the Alps. Water power was (and is) environmentally friendly, available in great quantities within our national borders and obtainable at low-cost: this range of benefits has, right from the outset, driven the country to invest heavily in hydropower. Until the 1920s, almost all of Italy's green energy came from hydropower plants, with only some very minor contributions from other sources like geothermal (with the Larderello plant in Tuscany, which was built in 1904) and wind. After initially being the undisputed star on the non-fossil fuel scene, the importance of hydropower has diminished over the decades, not because of a drop in production – in fact, it has never dropped – but due to a substantial and progressive flattening of the curve. The exploitation of the potential offered by Italian hydropower was at its greatest during the first half of the 1900s up to the end of the 1950s, during which time a succession of large power plants were built. Subsequently, however, partly due to the lack of further useful sources that could be utilized and partly through a loss in prestige following a series of environmental disasters such as the Vajont landslide, from the 1960s through to the first 20 years of the new century, the increase in production was somewhat limited. Over the last 60 years, the overall variation has remained below 10%, albeit with a succession of fluctuations which, alongside the growth in other energy sources, fossil or otherwise, has led to a significant drop in the relative importance of hydropower in Italy's energy mix. The number of hydropower plants in Italy and where they are located The total number of hydropower plants in Italy at the end of 2021 was 4,646 according to detailed reports from the electricity supplier GSE (Gestore dei Servizi Energetici). GSE also calculated a net growth of 143 plants (or +3.2%) between 2020 and 2021 with a capacity growth of 66.4 MW (+0.3%). In 2009 there were just 2,249 plants, and since then the number has effectively doubled, with the key years being 2010 (+480 plants), 2016 (+270) and 2017 (+348). However, this growth in numbers has not led to a commensurate increase in the amount of power generated, because the power plants are now smaller, on average, than they were in the past: indeed, the average annual increase in total power generated is just 0.7%. The installation of small power plants, so-called mini hydro plants, began in the early 2000s, and progressed to the extent that the average size of hydropower plants in Italy fell by around half from 8.4 megawatts per plant at the beginning of the century to just under half that (4.1 MW) in 2021. According to figures released at the end of 2021, the largest size class is that of plants with a capacity less than or equal to 1 MW (73.4%). This is followed by the class between 1 and 10 MW (20%). Overall, these two classes cover only 19% of the total installed capacity, while the 310 plants with a capacity greater than 10 MW account for the remaining 81% of total national hydropower capacity. Hydropower is not evenly distributed across Italy. The vast majority of power plants, and installed capacity, are located in the Alps. According to the same figures released at the end of 2021, there are 1,018 plants in Piedmont, which is more than a fifth of the total number in Italy, with a capacity of 2,799 MW, and 14.6% of the total amount of hydropower generated nationally. Next comes Lombardy with 721 plants, although it ranks first in terms of power generated, with 5,190 MW, or 27.1%. Then there are the autonomous provinces of Trento and Bolzano which, with 280 and 587 plants respectively, together account for 17.8% of Italy's total capacity. The ranking continues with Veneto (402 plants and 6.2% of capacity), the Aosta Valley (200 and 5.3%) and Friuli Venezia Giulia (257 and 2.8%). Along the Apennines, we must also mention Abruzzo, with just 75 plants, but 5.3% of the national capacity, Calabria (60 plants and 4.1%) and Umbria (49 plants and 2.8%). Finally, important contributions also come from Lazio, Campania, Sardinia, Tuscany, Emilia-Romagna and the Marche region. Taken together, Liguria, Molise, Apulia, Basilicata and Sicily account for just 2.5% of total installed capacity. The amount of energy produced, in absolute terms According to the data gathered by GSE at the end of 2021, Italy has a total hydropower installed capacity of 19.72 gigawatts, which is around 33% of the total national capacity deriving from green sources. In 2008, capacity was 17.6 gigawatts, with average increases from one year to the next of just above 0.1 gigawatts. In terms of energy produced, at the end of 2021, the annual amount from hydropower reached nearly 45.39 terawatt hours, a little over 14% of Italy's national energy demand and 39% of the energy produced from renewable sources. The fluctuations in energy produced from one year to another are determined by meteorological factors on the one hand, and by the new installation or decommissioning of large plants on the other. In 2017, for example, a particularly difficult year for hydropower production, the amount of energy produced was just 36.2 terawatt hours, but it then increased by 35% the following year. However, the geographical distribution of the energy produced remains fairly constant: approximately 76% comes from the northern regions, and the remaining amount is more or less equally divided between the center and the south. Interesting facts about Italian hydropower Some hydropower plants have an important place in the history of Italy. The first to mention, not least because it's the first chronologically, is the Bertini hydropower plant in Porto d’Adda on the Adda river in what is today the province of Monza and Brianza; it was built in 1895 and is one of the oldest hydropower plants still in operation today. The Vizzola power plant in the province of Varese also started operations around the late 1800s/early 1900s, with an industrial canal which draws its water from the Ticino river. Today, Italy's largest hydropower plant is in the small municipality of Entracque, in the province of Cuneo in the heart of the Maritime Alps. This Enel Green Power plant is called Luigi Einaudi and it was built in the 1970s before becoming fully operational in 1982. The power station is supported by three reservoirs: the Chiotas reservoir at an altitude of 2,000 meters, Lago della Rovina (Lake Rovina) at 1,500 meters and Lago della Piastra (Lake Piastra) at 1,000 meters. A long and complex underground network of pipes connects the reservoirs, transferring water all the way to the actual power station itself, which is dug into the rocks. Following the huge human, financial and technological effort required for its construction, the Einaudi currently has a capacity of 1.065 gigawatts, more than 5% of the total national capacity and comparable to that of the entire province of Turin. Other large Italian hydroelectric power plants that deserve a mention are the Edolo plant in the province of Brescia, with its altitude drop of more than 1,200 meters, and the Domenico Cimarosa plant in Presenzano in the province of Caserta, which, like Edolo, boasts a capacity of just under a gigawatt. One of the ways in which hydropower plants are classified today is on the basis of the so-called retention time, which is the average time the water remains in a reservoir before its gravitational potential energy is transformed into electricity by turbines and transformers. Hydropower plants are classified as storage power plants (seasonal), if the retention time is greater than 400 hours, pondage plants (daily or weekly) if the retention time is between 2 and 400 hours and run-of-river plants if the retention time is less than 2 hours, or there is no possibility of regulating the flow, as is the case with rivers. In Italy, this last type accounts for 28% of the total installed capacity and 46% of total production. Storage and pondage plants are roughly comparable to each other in terms of production, accounting for 25% and 27% respectively, although the former is 43% of installed capacity and the latter 29%. The future of hydropower Italian hydropower isn’t expected to have a future of exponential growth, unlike other sources of green energy. However, the prospects for development are still significant and very interesting, especially in terms of efficiency: today's technology and innovative solutions make it possible to transform almost all water energy into electricity, with values often reaching 70%-75% and sometimes as high as more than 80%. Given that most of Italy’s large hydropower plants are more than 70 years old, the amount of energy actually produced is impacted by at least three factors: the signs of ageing, the lack of plant modernization and the reduced potential of hydropower due to climate change. With respect to the last of these three factors, it is only possible to act globally through the energy transition and pollution reduction; however, it is estimated that upgrading the plants, even just through maintenance activities and minor equipment replacements, could lead to an annual increase of at least 5.8 gigawatts of capacity and 4.4 terrawatt hours of energy in just a few years, saving in excess of 2 million tons of carbon dioxide and creating 2,000 new jobs (direct and indirect) to carry out the work. New technologies and digitalization can even make the plants more flexible and long-lasting, through the use of predictive maintenance and IoT devices. From a technical standpoint, in addition to efficiency, the upgrades would primarily relate to guaranteeing good levels of output even with significant variations in water flow, as well as to the management of water and energy flows so as to ensure that demand is met. The classic example is at night when demand is low, during which time it's possible to use the excess energy generated to pump the water back up to a higher altitude, so that it can be used to generate more energy the following day. Finally, we’re working on sustainability: although hydropower is a completely green energy source, the plants themselves can have a negative impact on the environment. For that reason, solutions are being developed to enable these plants to become increasingly more integrated into the surrounding natural environment, thus reducing their impact on the local landscape and wildlife.

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How much hydroelectric energy is produced in Italy and where

How much hydroelectric energy is produced in Italy and where