Slovenia is preparing to embark on an ambitious energy project, aiming to build the largest floating solar power plant in Europe. According to pv-magazine, the state energy company Holding Slovenske Elektrarne (HSE) intends to construct the PSE Druzmirje facility with a capacity of 140 MW on the site of the former coal mining lake Druzmirje, located near Sostanj in the northern part of the country.
The plant will cover up to half of the reservoir created by years of lignite extraction.
The investment for this project is estimated at around $116.6 million. Financing will be sourced from HSE’s own funds, loans, and support from the EU Just Transition Fund. The company will retain ownership, while management will be handled by its subsidiary. PSE Druzmirje is set to become Slovenia’s largest solar project and one of the most powerful floating power plants in Europe.
Project leader Simon Chizmek states that spatial planning is currently underway. A government document detailing the plan is expected in the fourth quarter of this year. Discussions are ongoing with local authorities, and HSE emphasizes that financial and social benefits will be shared with the region's residents.
After construction, the coastal area is planned to be transformed into a recreational-social space, merging renewable energy development with new community amenities. Work is scheduled to commence in the third quarter of 2026, with electricity production expected to start in the first quarter of 2027. The plant is projected to generate up to 140 GWh of electricity annually, providing power for approximately 35,000 Slovenian households.
This project will surpass the record of the French floating power plant with a capacity of 74.3 MW, which was opened in June 2025. Slovenia’s solar energy market has primarily focused on residential, commercial, and industrial sites, while community-scale projects are still in their infancy.
The development of PSE Druzmirje symbolizes the country's shift towards large-scale grid-connected solar projects and demonstrates sustainable growth in renewable energy potential. By mid-2025, Slovenia's installed solar power capacity is expected to reach 1.5 GW, having increased by 85 MW in just the first six months. In comparison, 298 MW were added in 2024, and 400 MW in 2023.
Earlier this year, the Slovenian government approved the construction of a ground-mounted solar power plant with a capacity of 30 MW, to be implemented by the HSE subsidiary Dravska elektrarna Maribor. This reflects the gradual strengthening of the country’s position in the renewable energy sector.