Avče Pumped Storage Plant

BW

The pumped storage power plant Avče (Slovenian Črpalna Hidroelektrarna Avče, Che Avče short ) is located near the Slovenian village Avče that if Soci part of the channel community. Operator is SENG Soške elektrarne Nova Gorica doo

History

The project was approved on 1 August 2004 and broke ground for the pumped storage power plant Avče took place on 22 September 2004. Works contracts were awarded in December 2004 and construction began in January 2005. Actually, the power plant should be completed in December 2008, the commissioning however, only took place in April 2010. SENG Total invested 122 million euros in the construction of pumped storage power plant.

Technology

Upper basin

The upper basin north of Kanalski Vrh on the Banjšice Plateau. As this plateau is not completely closed, two dams of calcareous sandstone and limestone boulders were built. To prepare the water tightness of the surface of the upper reservoir was coated with asphalt concrete. The upper reservoir has a usable volume of 2.17 million cubic meters. The maximum water level in the upper basin is 625 m. i J.

Lower basin

As a basin at 104 m. i J. is also used of the existing storage space Ajba of the hydroelectric plant Plave in the Soča River. The 45 m high water castle consists of two chambers.

Water flow and pressure tunnels

From the upper basin to Krafhaus leads a 2216 m long pressure tunnel with a diameter of 2.6 m to 3.3 m in diameter This is an effective head of 521 m achieved.

Power house

The power house is located on the left bank of the river Soča. The power house is located in a circular shaft with diameter of 18 m and 80 m depth, a single vertically standing reversible Francis pump- turbine with 185 megawatts ( MW) turbine operation and 180 MW in pump operation. The water flow through the pump turbine is 34 m³ / s in pump mode and 40 m³ / s in turbine mode. The rated speed of the turbine is 600 min-1, but can be ( depending on the source ) varies by -2 % and 4 % or -4% to 6 %. For the conversion of electrical energy into mechanical energy and vice versa, an asynchronous motor generator comes with a power rating of 195 MVA ( megavolt-amperes ) are used.

Every year a electric power of 553 gigawatt-hours (GWh ) is required for pump operation, it will be issued in turbine mode again 426 GWh. This corresponds to an annual utilization rate of 77%.

Mains connection

The connection to the power grid at the 110 kV level is via a 200 MVA generator transformer.