HPP Doshnica

Hydroelectric plant (HPP) Dosnica is located on the river Dosnica in the Municipality Demir Kapija in southern Republic of Macedonia. It was commissioned in 1952.

The intake configuration of HPP Dosnica is Tyrolean, built of stone, located 9.5 km downstream to the machine room. It has a capacity of 2,1 m3/s. The width and height of the overflow threshold is 11 m and 3.25 m respectively. The water of river Dosnica is captured directly on the riverbed. From the intake water goes to the sludge plant and from there to the inlet channel with length of 4400 m and diameter of 1600 mm. To the water chamber, water goes through the intake tunnel with a length of 3400 m. The water chamber has a diameter of 7 meters and it is 10 meters deep, and the water is automatically stored with an average of 75% of the capacity of the tunnel. From the water chamber to the machine room water passes through a steel pipeline with length of 530 m. The intake pipe in front of the machine room branches into 3 parts for each of the three turbines.

The machine room is located south of the settlement Demir Kapija. The machinery room has three Pelton turbines with horizontal axis with a nominal flow rate of 0,8 m3/s and each is connected to a synchronous generator with static excitation and total installed capacity of 5,1 MW. Under the building there is the drainage through which the water that has passed through the turbines is discharged, part in the fish farm Dosnica, and the other part to the riverbed. From the generators the produced electricity is transmitted to the three oil transformers 6.3/35 kV and as such is transmitted via two 35 kV transmission lines to substations in Demir Kapija and Negotino.

Overall electricity production and management at HPP Dosnica is automated. The average annual electricity production is 18 GWh.

Net drop 232.7 m
Throughput 3x0.80 m3/s
Turbine type Pelton turbine with horizontal axis
Generator type Synchronous generator with static excitation
Installed capacity 5.1 MW
Efficiency coefficient 89%
Average annual output 18 GWh

Dosnica river, which is a tributary of Boshava river, starts from the slopes of Mount Kozuf on 1820 meters above sea level, from the source Momina chuka and has a length of 38,5 km. It has a total drop of 1.750 m and an average gradient of 45,5 ‰. Dosnica river basin covers an area of 193,4 km². Almost across the entire route, it cuts through a canyon-like gorge.

Demir Kapija gorge is protected area (since 1960) in the category - natural monument (III category according to IUCN) and it is of particular importance in terms of biodiversity. Dosnica river, which is a tributary of the Vardar River, with a length of 18 km features the following types of fish: stream trout, chub and barbel - krkush. Demir Kapija gorge is one of the richest ornithological reserves in Europe by the rare birds, various species of mammals, reptiles and insects. There are also rare and endemic species of plants.

Links

EVN Macedonia Elektrani DOOEL Skopje
Str. 11 Oktomvri 9
Skopje 1000 Macedonia
Phone +389 (0)2 3205 000