Integrating together a pumped-storage hydroelectric power plant and a modern battery storage represents a unique power-engineering project for increasing flexibility and efficiency of power grids in Slovakia and Europe. Slovenské elektrárne, as the only Slovak company included in to the ranking Europe’s Climate Leader, have been preparing such an innovative solution thanks to modernisation of the largest Slovak pumped storage hydroelectric power plant on Čierny Váh. The project has the potential to reduce the generated amount of CO2 emissions and enable better integration of electricity generation from renewables.
“The SE Integrator project positively presents our country, Slovakia. It shows that we have a vision and we can prepare and implement world-class projects and as a country we can lead not only in nuclear, but also in hydropower engineering. We are connecting it with the latest available technology in order to extend service life of the pumped storage power plant and increase energy security of Slovakia.”
─ Milan Ilčík, hydropower plants director
The power grid, with raising number of renewables connecting, faces the differences between forecast and real generation from these sources, which are hard to forecast. At the same time, the peak generation from photovoltaic power plants (particularly during the day) and minimum consumption at the same time, there is a large energy surplus and on the other hand, at the time when these sources don’t generate, there is a lack of electricity in the grid. Surplus or lack of electricity must be compensated using variable electrical equipment, able to store energy and then deliver it quickly into the power grid. This will be the role of the SE integrator.
SE Integrator has the statute of a “Project of Common Interest” (Projekt spoločného záujmu) and it has received at the beginning of 2025 support for the preparatory phase of the project from the European grant Connecting Europe Facility Studies in the amount of more than EUR 2 million. The public consultation on the project took place on Thursday 15 May 2025 in Kráľova Lehota Culture Palace. Professionals and lay public both participated. For more information on the project SE Integrator see the booklet.
With more than 70% share in the overall electricity production in Slovakia, Slovenské elektrárne, a.s. is the largest electricity producer in the country. After shutting down the last coal-fired power plant, at the end of the first quarter of 2024, it generates all its electricity without direct CO2 emissions. It operates 5 nuclear units, 31 hydroelectric power plants, and 2 photovoltaic power plants.
Company´s commitment to generate electricity from low carbon sources makes it the leader in sustainable energy generation in the Central and Eastern Europe. The Company was listed four times in the prestigious index Europe's Climate Leaders prepared by The Financial Times and Statista since 2021. In 2025, Slovenské elektrárne was included into the ranking as the only company from Slovakia.
Slovenské elektrárne, a.s. has two shareholders. The majority shareholder is Slovak Power Holding B.V. (SPH) owning 66% of the share capital. A 50% stake in the share capital of SPH was owned by Energetický a průmyslový holding (EPH) and the remaining 50% is owned by the biggest Italian company Enel. The share of the Slovak Republic in Slovenské elektrárne represents 34%.
In December 2024, Enel and EPH signed an agreement under which EPH, as foreseen by the early redemption option, will purchase 50% of the share capital currently held by Enel in SPH. The closing of the transaction, which is expected in the first half of 2025, is subject to meeting certain conditions, including regulatory approvals.
