Slovenian state-owned power company Holding Slovenske Elektrarne (HSE) is developing a 140 MW floating photovoltaic (PV) plant on Lake Družmirje, located near Šoštanj in northern Slovenia. Formed by decades of lignite mining, half of the lake’s surface will be covered by the PSE Družmirje floating solar project. Upon completion, it is set to become Europe’s largest floating PV installation.
Simon Čižmek, the project manager for the floating PV plant, told pv magazine: “Agreements with local governments are progressing, and we are optimistic about the outcome. We look forward to sharing the economic and other benefits of the project with local residents in various ways.” Spatial planning is currently underway, with the spatial plan decree expected to be issued in the fourth quarter of 2025. Public consultations were held earlier this week to engage with the community.
The project, with an estimated cost of €100 million (approximately $116.6 million), will be funded through HSE’s own resources, loans, and support from the EU’s Just Transition Fund. HSE will fully own the project, with its subsidiary HSE SaŠa responsible for operation and management. Construction is scheduled to begin in the third quarter of 2026, and electricity generation is expected to commence in the first quarter of 2027. As a state-owned project, it will strictly adhere to EU public procurement regulations.
Once operational, PSE Družmirje is projected to generate 140 GWh of electricity annually, sufficient to power approximately 35,000 Slovenian households. The lakeshore area will also be transformed into a recreational and social space for the local community, enhancing the comprehensive benefits for the region. The project will surpass the current largest floating PV array in Europe—the 74.3 MW plant commissioned in France in June 2025.
As the largest solar project under development in Slovenia, PSE Družmirje marks a significant advancement for the country’s PV market. Currently, Slovenia’s PV market is primarily driven by residential and commercial installations, with utility-scale projects just beginning to emerge. By mid-2025, Slovenia’s total installed PV capacity reached 1.5 GW, with 85 MW added in the first half of 2025, 298 MW added in 2024, and 400 MW added in 2023. Another notable project is the 30 MW ground-mounted PV plant approved in May 2025 for HSE subsidiary Dravska elektrarna Maribor, reflecting progress in the utility-scale segment.
The Družmirje project underscores Slovenia’s strong commitment to expanding renewable energy through innovative solar solutions, supporting local communities, and advancing sustainable development.
