Hydroelectric energy

How we turn water energy into electricity.

In addition to being the most mature of the renewable technologies, hydroelectric energy is also the most abundant: globally, its installed capacity and production levels are far superior to those of any other renewable source. It is also the only sustainable energy that can be regulated as needed through the use of water storage solutions like dams and reservoirs.

Guaranteeing a safe, affordable and sustainable energy supply, in Europe the advantages of hydroelectric energy are increasingly well documented.

The CVA Group owns and directly manages one of the biggest Italian hydroelectric portfolios, consisting of 6 large dams, 61 intakes (33 of which classified as regional dams), more than 210 km of channels, about 50 km of penstocks and 32 power plants with 74 hydroelectric units. The plant portfolio, with total power of 934.5 MW, produces around 2.9 million MWh of clean energy every year: the company is one of the leading national producers in the sector and therefore places Val d’Aosta among the leading regions in Italy in the generation of energy from renewable sources. The hydroelectric power plants, with their dams, reservoirs and channels, are a widespread presence in the lateral and central valleys of the region.

Hydroelectric energy is obtained from the power of water, a 100% renewable source.

It is produced using the gravitational potential energy of a mass of water available in a basin at a certain height, which can be transformed into:

  • pressure energy, the value of which increases in the penstock connecting the reservoir and the turbine depending on the value of the existing height difference;
  • kinetic energy, possessed by the water particle when it is freed at the bottom of the pressurised penstock;
  • mechanical rotational energy, resulting from the work carried out by the pressure and/or velocity of the water on the turbine rotor;
  • electrical energy, resulting from the rotation of the electromagnetic part, dragged by the turbine into the alternator.

Hydropower is acquired from rivers and lakes through the construction of dams or weirs, from where it is then conveyed to production plants through canals and penstocks.
Power plants fuelled by water taken directly from rivers, known as "run-of-river" power plants, transform water energy into electricity, which is immediately fed into the transmission and distribution network as it cannot be stored.

Because it cannot be stored and transmitted over time, the potential energy of water is accumulated in lakes or reservoirs. From here, through penstocks, it is conveyed downstream to turbines where it is converted into electricity, as and when required, in power plants known as "basin or reservoir" power plants.

Wind energy

The wind, along with the sun and water, is one of the main renewable sources from which 100% clean energy can be obtained.

Wind energy is a key part of the decarbonisation process taking place at European level. According to the forecasts, the number of wind farms in Europe will rise in order to meet the ambitious target of making renewables our leading energy source, taking over from fossil fuels.

Through its subsidiaries, the CVA Group produces an average of around 320,000 MWh of wind power, meeting the average energy needs of approximately 112,000 households. The wind power is generated through 8 wind farms located in the Val d’Aosta (3 wind turbines), Lazio (21 wind turbines), Puglia (30 wind turbines), Tuscany (4 wind turbines) and Campania (11 wind turbines).

From the power of the wind we obtain wind energy, a completely sustainable alternative energy source.

Between an area of high atmospheric pressure and an area of low atmospheric pressure, its moving air mass possesses kinetic energy which can be transformed into:

  • mechanical rotational energy, resulting from the work carried out by the thrust of the wind on the turbine blades;
  • electrical energy, resulting from the rotation of the electromagnetic part, dragged by the turbine into the alternator.

The intensity or speed of the wind for wind energy use depends on many factors, such as the different pressures of the areas between which it moves and the conformation of the Earth's surface.

Wind was one of the earliest natural energies used by humans and, after years of neglect due to the advent of fossil fuels, its energy is once again regarded as important because it is clean and renewable.

Photovoltaic energy

Photovoltaic systems are able to transform solar energy into renewable electrical energy.

Today, photovoltaic is both the most popular and the most versatile source of energy among EU citizens and, considering the continuous price reductions, is an increasingly affordable technology option for achieving the decarbonisation of the energy sector. The growth in the number of solar power plants can be observed right across the EU with 26 of the 27 Member states installing more solar power facilities in 2019 than the previous year.

Every year the CVA Group produces an average of about 16,000 MWh through four photovoltaic plants consisting of more than 54,000 modules located in the Valle d'Aosta and Piedmont. The Alessandria Sud (15 hectares of land for 31,780 photovoltaic modules), Valenza Fornace (14 hectares of land for 21,840 photovoltaic modules) and La Tour plants (777 photovoltaic modules) produce enough energy to meet the average requirement of about 5,600 households. The fourth plant is located on the roof of the Company Headquarters and is composed by 216 solar panels, to provide a total power of 0,046 MW.

Technology allows solar energy to be used for different purposes (thermal, electrical...) and its transformation is influenced by cloud cover, variability and the intermittency of exposure cycles (day - night).

Solar energy can be used through photovoltaic conversion, which is carried out physically thanks to a series of crystal silicon modules (solar panels), directed to optimise irradiation and arranged in distanced rows to facilitate farming and grazing activities on the land on which they are located.

Individual panels have a rating of a few hundred Watts and, when properly connected, can be used to create plants with significant MW capacity and production levels of close to 10 million kWh/year.

Last update: Jun 13, 2022 11:54:42 (GMT+2)