Slovenia utility DEM plans 60MW battery storage co-located with hydroelectric plant & new PHES unit

LinkedIn
Twitter
Reddit
Facebook
Email

Slovenia state-owned utility Dravske elektrarne Maribor (DEM) is planning two battery storage units totalling 60MW co-located with an existing hydroelectric unit, as well as a new pumped hydro energy storage (PHES) plant.

CEO Damjan Seme gave the updates in an interview released on DEM’s site last week (31 January), in which he spoke at length about the energy transition in the country, which borders Italy, Croatia, Austria and Hungary. DEM is part of the larger state-owned power group HSE Group.

Seme said that the company last year submitted a building permit application for the installation of two 30MW battery energy storage systems at the Mariborski Otok Hydro Power Plant, which also has a power capacity of 60MW. He expects the permit to be granted within the first quarter of 2023.

He added that it was still to be decided whether the battery storage units would only provide services required within the HSE Group’s network, which includes various power generation units as well as energy trading in Slovenia and internationally, or “more widely on the market”.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

2022 also saw DME produce a feasibility study for the 440MW ČHE Kozjak pumped hydro energy storage (PHES) project. He didn’t reveal the planned capacity of the project but PHES typically has a duration of 6-20 hours implying anywhere between 2.6GWh and 8.8GWh.

“The continuation of the ČHE Kozjak project was extremely accelerated last year, the “frequency” of activity rose sharply due to the needs for the responsiveness of the power system, the needs for the supply of electricity to the market and, last but not least, the need for such a production unit due to the reliability of the network in relation to new consumers and new production units from renewable sources, which represent volatile sources,” Seme said.

He concluded that “…we must all do everything together to ensure” that the unit goes online by the end of the decade.

Energy-Storage.news covered two battery storage projects in Slovenia a few years ago totalling 52MWh of capacity developed by local firm NGEN, while the country is also participating in a 50MWh battery storage trial aimed at increasing grid flexibility between it and neighbour Croatia.

Energy-Storage.news’ publisher Solar Media will host the eighth annual Energy Storage Summit EU in London, 22-23 February 2023. This year it is moving to a larger venue, bringing together Europe’s leading investors, policymakers, developers, utilities, energy buyers and service providers all in one place. Visit the official site for more info.

3 November 2026
Málaga, Spain
Understanding technology and supplier selection for Europe’s utility-scale PV market in 2027. PV ModuleTech Europe 2026 is a two-day conference that tackles these challenges directly, with an agenda that addresses all aspects of PV module, inverter and battery supplier selection; product availability, technology offerings, supply chain traceability, quality assurance, factory auditing, system reliability, and supplier bankability.

Read Next

October 19, 2026
New Zealand energy storage company ArcActive has switched on a pilot lead-acid BESS in Victoria, Australia, with support from Origin Energy.
October 16, 2026
Australian energy company AGL has referred a 500MWh battery energy storage system (BESS) in Queensland to the federal government under Australia’s Environment Protection and Biodiversity Conservation (EPBC) Act.
October 15, 2026
Insufficient progress has been made towards the Energy Storage and Grids Pledge, endorsed by dozens of countries at COP29 two years ago.
October 15, 2026
960MWh Summerfield BESS in South Australia enters commissioning, while Gotion starts building the 843MWh Lower Wonga project in Queensland.
October 14, 2026
South Africa continues its push for energy storage capacity, with utility and grid operator Eskom issuing a call to work on a 21GWh pumped hydro energy storage (PHES) project.