Advancing green energy with the Otočac small hydropower plant
Otočac Small Hydropower Plant (SHP) project represents a significant milestone, being the first commercial deployment of our newly developed turbine-generator unit.
The contract for this landmark project was signed on October 11, 2022, a joint venture of HEP and KONČAR.
Nestled in the Lika-Senj County near Otočac, SHP Otočac will become part of the Senj Hydropower System (HES Senj), which harnesses the hydro potential of the Lika and Gacka rivers as they descend from the Lika Plateau to the Adriatic Sea. A critical design priority for SHP Otočac is ensuring the uninterrupted operation of the Senj Hydropower Plant (HPP), regardless of the SHP’s operational status. To achieve this, a spillway will be constructed on the Lika Canal, channeling water toward the SHP intake. If SHP Otočac is offline, the spillway will maintain water flow through the Lika–Gacka Tunnel, preserving its full capacity and efficiency.
At the core of SHP Otočac is cutting-edge technology: a Kaplan turbine with variable rotational speed paired with a permanent magnet generator, both products of KONČAR’s intensive R&D efforts. This dual-regulation system, controlling both flow and rotational speed, ensures seamless performance under changing flow rates or head conditions. Supporting this innovation is KONČAR – Electronics and Informatics’ newly developed frequency converters, enabling grid connection with precision. These advanced converters feature a rated voltage of 3x690 VAC, a rated current of 418 A, a 50 Hz network frequency, and a water-to-water heat exchanger for efficient cooling. With an average head of 3 to 6 meters and an installed flow capacity of 3x16 m³/s, SHP Otočac will boast a total installed capacity of 1.5 MW, comprising three units of 500 kW each.
The project draws on the collective expertise of several KONČAR companies. KONČAR – Distribution and Special Transformers will supply high-performance transformers (5TBNO 2000-36x/AAA and 5TBNp 100-36x/AAA), while KONČAR – Digital will implement a SCADA system for advanced plant control. Our KSMA medium-voltage switchgear will also be a key component of the infrastructure.
Expected to be operational by 2025, SHP Otočac will deliver over 7 GWh of clean energy annually, contributing to the region’s green energy transition. By leveraging renewable sources such as hydro, KONČAR continues to drive sustainable innovation and reinforce its leadership in the renewable energy sector.