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Moste Hydroelectric Power Plant

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Moste Hydroelectric Power Plant

Završnica Hydroelectric Power Plant

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History

1914:
HPP Završnica on the Završnica stream is built

1952:
HPP Moste begins operating as the first power plant on the Sava River. The power plant is designed as a storage power plant for peak energy production. In the HPP Moste power plant, three units (Francis turbines) with a total capacity of 28.5 m3/s were originally installed. Due to the Sava River carving a deep canyon in the upper reaches into erodible rocks (conglomerate, moraines) overlying an impermeable (Tertiary and Triassic) substrate, the entire area is located on Tertiary overconsolidated clay (silt), which, due to unfavorable geomechanical properties, causes numerous problems in hydrotechnical facilities. To ensure the sealing of the accumulation basin, 351 meters of sealing curtains were installed to the impermeable base at depths of up to 120 meters.

1964:
The dam of HPP Moste is raised by 1.25 meters using a wooden provisorium, increasing the available volume by 15%. There are four fields on the dam with a capacity of 570 m3/s.

For the evacuation of peak waters and emptying the reservoir, a bottom outlet is located on the right side. The inlet structure is located on the left side of the dam, and from there, an inlet tunnel with a length of 840 meters leads to the power plant. The inlet tunnel also conveys return waters from the Završnica stream. In the fully embedded power plant, all hydromechanical, mechanical, and electrical equipment is installed. An outlet tunnel with a length of 1.5 kilometers and a diameter of 4 meters leads from the power plant to the outlet into the Sava River. The control room and the 110/6.3 kV and 110/20 kV substations are located on the terrace above the power plant.

1977:
A fourth unit with a capacity of 6 m3/s is added to the HPP Moste power plant. The supply pipeline from HPP Završnica is connected to HPP Moste, allowing increased production. The system was designed to enable the pumping of Sava River water into the higher-lying Završnica reservoir during times of excess energy production, but this was never realized due to pollution in the Sava River.

1999:
The dam of HPP Moste is renovated. Due to the unrealized pumping project and unreliable test unit equipment with poor efficiency, Unit 4 was reconstructed in 1999. As part of the reconstruction of the unit, the runner, guide vanes with a new hydraulic shape, turbine governor, and all auxiliary technological equipment were replaced. On the electrical side, a new proprietary use of the unit was developed, the excitation system was replaced with a static excitation system with digital control and microprocessor control, a new unit protection system with numerical and multi-microprocessor structure was installed, and a distributed microprocessor system for local and remote unit control from the remote control center of SEL was also installed. Within the reconstruction of the unit, its ecological remediation was also carried out, during which all bearing seats were made with self-lubricating bushes and DEVA segments. An oil separator was installed for pumping drainage water from the unit area, which cleans all water before exiting the facility.

2008 – 2010:
Renovation of HPP Moste is carried out. The construction renovation of the power plant was aimed at preventing further deformation of the facility. The units were replaced from 3.5 MVA, 3×5.5 MW to 2×9 MVA, 2×7 MW. The capacity changed from 3×9.5 to 2×13 m3/s. As part of the power plant renovation, most of the auxiliary equipment and all secondary equipment of the power plant were replaced. The 110/35/20 kV substation was reconstructed into the 110/6.3 kV SEL and 110/20 kV Eles substations, Elektro Gorenjska. The air-insulated 110 kV substation was discontinued and replaced with a new gas-insulated substation. The 35 kV substation was discontinued. Instead of the 35/6 kV blocks, a transformation into 110/6 kV and the 110/20 kV distribution RTP were established. The entire system provides 21 MW of power during peak production, with an average annual production of 56 GWh.

For Technical Enthusiasts

Moste 4 Moste 1,2
Useful Volume of Reservoir 123.000 m3 2.845.152 m3
Installed Flow 6 m3/s 26 m3/s
Power at the Dam 8 MW 13.5 MW
Average Annual Flow 0.7 m3/s 13.6 m3/s
Average Annual Production 5 GWh 60 GWh
Year of Commissioning 1916 1952
Turbine Type Francis Francis
Number of Turbines 1 2
Rated Power of Power Plant 11 MVA 18 MVA
Gross Head (Water Drop) 177.2 m 70.45 m

Mavčiče Hydroelectric Power Plant

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Mavčiče Hydroelectric Power Plant

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History

1981:
Construction of the Mavčiče hydroelectric power plant began.

1987:
The Mavčiče hydroelectric power plant started operating on July 31, 1986. Just three months later, at the end of October, the second unit was successfully commissioned.

In the Sorško field, under Kranj, the Sava River flows in a valley it carved into highly permeable Quaternary deposits (conglomerate). The depth of the impermeable layer is 120 meters below the surface. Beneath the Sorško field lies a rich aquifer, fed by the Sava River, which serves as a potential water source for central Slovenia. Because the dam is entirely founded on permeable rock formations, it was necessary to install a sealing curtain to the impermeable foundation, which extends along the sides of the dam for a length of 200 meters.

The Mavčiče Hydroelectric Power Plant is a run-of-the-river plant with a dam structure comprising the powerhouse, spillways, and a gravity earth dam. The structural height is 40 meters. Inside the powerhouse, two units (Kaplan turbines) with a combined discharge capacity of 260 m3/s are installed. They produce 38 MW of power at peak production and 62 GWh at the average annual production rate.

The spillway structure consists of two overflow fields equipped with segmental barriers and hinged gate. The dam height is 19.5 meters. The discharge capacity of one overflow field is 1600 m3/s (for a 100-year flood).

The power plant is equipped with two synchronous generators with a rated capacity of 25 MVA and a voltage of 10.5 kV. Each generator is connected to the 110 kV grid through the power plant’s 110 kV switchgear. The power plant is remotely controlled from the SEL control centre, located in Medvode.

2011:
In 2011, the 110 kV switchgear was updated, enabling the connection to the 110 kV grid. By the end of the year, the secondary equipment of the hydroelectric plant was also updated.

For Technical Enthusiasts

HPP Mavčiče
Useful Volume of Reservoir 1.665.000 m3
Installed Flow 260 m3/s
Power at the Dam 38 MW
Average Annual Flow 64.2 m3/s
Average Annual Production 68 GWh
Year of Commissioning 1986
Turbine Type Kaplan
Number of Turbines 2
Rated Power of Power Plant 50 MVA
Gross Head (Water Drop) 17.5 m

Medvode Hydroelectric Power Plant

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Medvode Hydroelectric Power Plant

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History

1947:
Construction began in 1947, with both Slovenian and Yugoslavian workers participating in the construction. In addition to the construction of the power plant itself and the dam, workers also built a complex of residential buildings.

1953:
A hydroelectric power plant with a dam was established after the Zbilje Lake was formed due to the rising water level of the river. The dam is located at a point where the Sava River carved rapids into the dolomite, which is largely cracked and filled with cavities. A sealing curtain was installed to the impermeable base, which extends along the sides of the dam to a depth of 27 to 45 meters. The dam structure combines a pillar-shore type. In the direction of the riverbed, there are two overflow fields equipped with double-panel sluice gates of hook design, with a damming height of 17.5m. The flow capacity of the overflow fields is 2400 m3/s.

1964:
The floodgates were raised by 1 meter, increasing the power of the turbines by 11%. In the turbine housings, along the riverbank, two units (Kaplan turbines) with a total flow rate of 150 m^3/s were installed, providing 25 MW of power at peak production and an average annual production of 72 GWh.

1994 in 1995:
The power plant was renovated, and the generators were replaced. It is equipped with two synchronous generators with a nominal power of 13.5 MVA and a voltage of 6.3 kV. The generators are connected to the 6/110 kV switchgear.

2003 in 2004:
The power plant was modernized, and the turbine and secondary equipment were replaced. The 110 kV switchgear was upgraded with a 2×110/6.3 kV transformation and a 110/20 kV distribution switchgear owned by Elektra Gorenjska.

For Technical Enthusiasts

HPP Medvode
Useful Volume of Reservoir 1.185.000 m3
Installed Flow 150 m3/s
Power at the Dam 25 MW
Average Annual Flow 65.1 m3/s
Average Annual Production 77 GWh
Year of Commissioning 1953
Turbine Type Kaplan
Number of Turbines 2
Rated Power of Power Plant 27 MVA
Gross Head (Water Drop) 21.2 m

Vrhovo Hydroelectric Power Plant

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Vrhovo Hydroelectric Power Plant

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History

1989 – 1993:
Construction of HPP Vrhovo, located in the field below the Vrhovo settlement, marks the first in a series of hydropower plants in the lower Sava cascade. The dam structure is of concrete-gravity type with a structural height of 27 meters. The power plant operates in a daily-flow regime with accumulation, serving as the headwater reservoir for the lower Sava cascade. After the completion of the entire cascade of hydropower plants on the Sava River, this reservoir will serve as an intermediate balancing reservoir.

Downstream from Radeče, the river valley widens into a broad field where the Sava River transitions into a valley flow regime. The foundation consists of impermeable Permian-Carboniferous shales, overlaid by Quaternary sediment of gravelly-sandy nature, with a top layer of sandy marls and humus. The dam structure is founded on impermeable shales, and the foundation slab is entirely drained. Sealing of the high-water banks is accomplished with thin-wall concrete walls.

The dam structure consists of, in sequence: the power plant, five spillways, and connecting earthen embankments. The power plant houses three units (penstock turbines) with a total flow capacity of 500 m^3/s. At peak production, they provide 34.2 MW of power, with an average annual production of 116 GWh. The spillway gates are equipped with segmental stoplogs and have a damming height of 10.5 meters. The flow capacity of the spillways is 3100 m^3/s, equivalent to a 100-year flood.

The power plant is equipped with three synchronous generators with a nominal power of 14.3 MVA each at a voltage of 6.3 kV. They are connected to the 110 kV grid via a transformer (45 MVA, 119/6.3 kV) with the possibility of connecting.

For Technical Enthusiasts

HPP Vrhovo
Useful Volume of Reservoir 1.165.000 m3
Installed Flow 500 m3/s
Power at the Dam 34 MW
Average Annual Flow 229 m3/s
Average Annual Production 120 GWh
Year of Commissioning 1993
Turbine Type Kaplan – tube
Number of Turbines 3
Rated Power of Power Plant 42,9 MVA
Gross Head (Water Drop) 8,80 m

Small solar power plant Mavčiče

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History

2007:
SPP Mavčiče is commissioned

SPP Mavčiče consists of:

  • 210 PV modules with a power of 170 W each, installed on the southern facade of the HPP Mavčiče building.
  • 210 PV modules with a power of 170 W each, installed on the roof of the HPP Mavčiče building.

The installed capacity of the solar generator is 71.4 kW. The anticipated annual production is approximately 72 MWh of electrical energy.

For Technical Enthusiasts

Technical data
SPP Mavčiče
solar generator installed power 71,4 kWp
number of PV modules 2 x 210
power of each module 170 Wp
type od modules Schott Solar ASE 170
location J facade of HPP Mavčiče building
number of inverters 12
power of each inverter 6 kW
type of inverters Sunny Mini Central 6000
communication and monitoring Sunny Web Box
anticipated annual production 72 MWh
start of electricity production 1st phase: June 2006, 2nd phase: May 2007

Small solar power plant Medvode

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History

2008:
SPP Medvode is commissioned

SPP Medvode consists of 280 PV modules with a power of 210 W each, installed on the roof of the maintenance center of HPP Medvode. The installed capacity of the solar generator is 58.8 kW. The anticipated annual production is approximately 60 MWh of electrical energy.

For Technical Enthusiasts

Technical data
SPP Medvode
solar generator installed power 58,8 kWp
number of PV modules 280
power of each module 210 Wp
type od modules Sanyo HIP – 210
location Roof of the HPP Medvode maintenance center
number of inverters 6
power of each inverter 11 kW
type of inverters Sunny Mini Central 11000 TL
communication and monitoring Sunny Web Box
anticipated annual production 60 MWh
start of electricity production July 2008

Small solar power plant Vrhovo

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History

2008:
SPP Vrhovo 1 started operating. SPP Vrhovo 1 consists of 360 PV modules with a power of 215 W each, installed on the roof of the machine room of HPP Vrhovo.

The installed capacity of the solar generator is 77.4 kW, and the anticipated annual production is approximately 74.6 MWh of electrical energy. SPP Vrhovo 2 consists of 1584 PV modules with a power of 224 W each, installed on the right-bank dam of the reservoir of HPP Vrhovo.

The installed capacity of the solar generator is 355 kW, and the anticipated annual production is approximately 404 MWh of electrical energy.

2010:
SPP Vrhovo 2 started operating

For Technical Enthusiasts

Technical data
SPP Vrhovo
solar generator installed power 77,4 kWp
number of PV modules 360
power of each module 215 Wp
type od modules Sanyo HIP – 215
location streha strojnice HPP Vrhovo
number of inverters 9
power of each inverter 8 kW
type of inverters Sunny Mini Central 8000 TL
communication and monitoring Sunny Web Box
anticipated annual production 74,6 MWh
start of electricity production January 2008

Small hydroelectric power plant Mavčiče

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History

1987:
Small HPP Mavčiče starts operating. It is located on the southern side of the Sava River, at the water inflow into the fish spawning ground.

The small power plant is equipped with a single unit that operates in parallel with the grid, supplying all available energy based on the prescribed constant water inflow of 0.5 m³/s.

In the powerhouse building of the small hydroelectric power plant, there is a unit comprising a horizontal spiral Francis turbine directly connected to an asynchronous generator via an elastic coupling. The turbine guide vanes consist of movable control blades surrounding the runner and regulating the flow. The adjustment of the blade opening is done manually according to the required flow. The runner is cast from aluminum bronze and is directly fitted and cantilever-mounted on the turbine shaft, which is supported by two roller bearings attached to the turbine cover. An asynchronous standard motor is used for the generator.

For Technical Enthusiasts

Technical Data
sHPP Mavčiče
rated power of asynchronous generator 90 kW
rated voltage of asynchronous generator 380 V
maximum power of the turbine 70 kW
power of the sHPP at the generator terminals 66 kW
constant water flow 0,53 m3/s
available water head 15,8 m
type of turbine Francis horizontal spiral
rated rotational speed 750/min
average annual production 340 MWh
start of electricity production January 1987

Small hydroelectric power plant Vrhovo

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History

2008:
Small HPP VRHOVO started operating. It is located on the southern side of the Sava River at the water inflow into a fish spawning ground.

The small power plant is equipped with a single unit that operates in parallel with the grid, supplying all available energy based on the prescribed constant water inflow of 0.5 m³/s.

The turbine is a vertical, non-regulated, pipe propeller design. The runner is a propeller of modern hydraulic shape with four fixed blades attached to the runner hub. The turbine shaft is supported between the guide bearing and the combined turbine bearing. The guide bearing is submerged in water and lubricated with water. The combined bearing is located in the generator’s support housing and consists of radial and axial roller bearings. Lubrication of this bearing is done with grease. Power transmission from the turbine to the generator is designed to use an elastic coupling. An asynchronous standard motor is used for the generator.

For Technical Enthusiasts

Technical Data
sHPP Vrhovo
rated power of asynchronous generator 30 kW
rated voltage of asynchronous generator 0,4 kV
rated power factor 0,85
power of the sHPP at the generator terminals 22 kW
constant water flow 0,5 m3/s
available water head 5,55 m
type of turbine propeler
rated rotational speed 1000/min
average annual production 184,8 MWh
start of electricity production March 2008

Small hydroelectric power plant Borovlje

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Small hydroelectric power plant Borovlje

Savske elektrarne Ljubljana d.o.o.

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Company Presentation Video of SEL d.o.o.

Historical Video about the Electrification of Slovenia.