The Edolo Pumped Storage Plant is located along the

Oglio River The Oglio (; or ; , ) is a left-side tributary of the river Po in Lombardy, Italy. It is long. In the hierarchy of the Po's tributaries, with its of length, it occupies the 2nd place per length (after the river Adda), while it is the 4th pe ...

just downstream of

Edolo Edolo ( Camunian: ) is a town and ''comune'' in the province of Brescia, Lombardy, northern Italy, located in the upper Camonica valley. Edolo is neighbour to the comuni of Corteno Golgi, Incudine, Lovero, Malonno, Monno, Ponte di Legno, Sav ...

Brescia Province The province of Brescia (; Brescian: ) is a province in the Lombardy region of Italy. It has a population of some 1,265,964 (as of January 2019) and its capital is the city of Brescia.With an area of 4,785 km2, it is the biggest province of ...

in the

Lombardy The Lombardy Region (; ) is an administrative regions of Italy, region of Italy that covers ; it is located in northern Italy and has a population of about 10 million people, constituting more than one-sixth of Italy's population. Lombardy is ...

region of Italy. Using the

pumped-storage Pumped-storage hydroelectricity (PSH), or pumped hydroelectric energy storage (PHES), is a type of hydroelectric energy storage used by electric power systems for load balancing. A PSH system stores energy in the form of gravitational potent ...

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

method, it has an installed capacity of . Its generators were commissioned between April 1984 and November 1985. Lake Avio was previously completed in 1929 and Lake Benedetto completed in 1940.

Design and operation

The lower reservoir is located in Edolo on the north bank of the Oglio. It was created by a circular dike and stores water for pumping. Of the lower reservoir's storage capacity, can be used for pumping. It is located at an elevation of . The upper reservoir, Lake Avio, is located east of Edolo high in the mountains at . Directly above Lake Avio is Lake Benedetto which supplements Avio with water. Both the Avio and Benedetto Dams are

gravity dam A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation. Gravity dams are designed so that each section of the dam is ...

s and are and in height, respectively. The total storage capacity of the upper reservoir (including Lake Benedetto) is of which can be used for power generation. The elevation of Lake Avio is above sea level and it traps water from a

catchment area A catchment area in human geography, is the area from which a location, such as a city, service or institution, attracts a population that uses its services and economic opportunities. Catchment areas may be defined based on from where people are ...

. Connecting the upper and lower reservoirs is a series of tunnels and pipes. Beginning at Lake Avio's intake, an long head-race tunnel transfers water east before it bifurcates into two long

penstock A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydro turbines and sewerage systems. The term is of Scots origin, and was inherited from the earlier technology of mill pond ...

s. Each penstock reaches the power plant and splits further to supply the eight pump-generators with water. The lower reservoir and power plant are connected by two long tunnels. The difference in elevation between both reservoirs affords a

hydraulic head Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a. It is usually meas ...

of . At the power station, each Francis pump-turbine-generator is rated at 125 MW for power generation and 140 MW for pumping. Only seven of the pump-generators can operate at one time. When energy demand is low and electricity cheap, the plant pumps water from the lower reservoir to the upper. When demand is high, that water, being stored energy, is released back down the same tunnels and pipes to the plant for generation. After being used for generation, the power plant sends the water back to the lower reservoir. New water reserves can also be taken from the Oglio River. This process repeats as needed and allows the plant to serve as a

peaking power plant Peaking power plants, also known as peaker plants, and occasionally just "peakers", are power plants that generally run only when there is a high demand, known as peak demand, for electricity. Because they supply power only occasionally, the powe ...

. The plant generates 737 GWh annually but consumes 1,021 GWh pumping. Although it consumes more energy than it creates, pumping occurs at night, when electricity is cheap. This makes the plant economical, as it generates electricity during high demand, more expensive periods. The size of the Avio Dam's catchment area allows it to collect water naturally as well and 219 GWh can be generated from this water alone annually.

References

{{reflist Dams completed in 1984 Energy infrastructure completed in 1985 Dams in Italy Hydroelectric power stations in Italy Pumped-storage hydroelectric power stations in Italy

Design and operation

See also

References