The “Pirot” hydropower plant is located on the territory of South-Eastern Serbia, between the city of Pirot and Bulgarian border and utilizes the water from the Visocka River at the “Zavoj” dam profile. The “Zavoj” reservoir is a natural reservoir.
HPP construction works started in 1983 and the first unit started with operation in 1990.
The “Pirot” HPP most important characteristics with appurtenant structures are given below:
- Reservoir
| Length | 17 km |
| Area | 550 ha |
| Total volume | 170 million m3 |
| Maximum operating water level | 616 m a.s.l. |
- Conduit
| Tunnel diameter | 4,5 m |
| Tunnel length | 9,093 m |
- HPP
| Type | storage, diversion |
| Maximum net head | 243.7 m |
| Minimum net head | 180 m |
| Installed discharge | 45 m3/s |
| Installed power | 2 x 40 = 80 MW |
| Number of units | 2 |
| Annual number of operating hours | 1,400 |
(Source: PU EPS Web site)