1. What electricity storage projects have been commissioned in your jurisdiction to date?

There are no major electricity storage projects in Slovenia with the exception of the hydroelectric pumped storage facility Avče (which has a capacity of 185 MW) on the Soča River, which is (ultimately) state owned. Nevertheless, the need for the storage of electricity, especially co-located with existing renewable sources (such as solar, wind) coupled with potential subsidies envisaged in consultation documents, could trigger future investment in this area. It seems that domestic batteries are not yet directly discussed though. 

As side from major projects, there have been some smaller projects including the vanadium-flow batteries installed at a restaurant in the Slovenian Alps. Whilst small they demonstrate how useful the technology can be when combined with on-site generation.

2. What electricity storage projects are anticipated in your jurisdiction in coming years?

More recently, the interest for planning and construction of pumped storage projects is increasing amongst the sector of energy producers and foreign investors. Further, as a supplement to existing renewable energy facilities, storage of electricity could be a great benefit to stabilise the electricity released from these variable sources of production and consequently variable inputs.

3. Is there any specific legislation/regulation or programme that relates to energy storage in your jurisdiction?

Electricity storage is not specifically considered within the Slovenian legislative framework. No subsidies are envisaged by the current legal framework, but are mentioned within the Action Plan for Energy Efficiency within the period of 2014 – 2020 as enhancing the efficiency of distribution systems for which subsidies are envisaged in the future until 20201. Subsidies coupled with the need for storage of electricity and combined with potentially lower costs of storage in the future could trigger investments in Slovenia.

4. Please give examples of challenges facing energy storage projects in your jurisdiction and how current projects have overcome these challenges.

Regulatory related challenges 

Given the lack of special status of energy storage and the lack of subsidies, there are pending regulatory burdens and potential disadvantages for investors interested in this particular field. 

Depending on technology used (for example pumped storage) storage of electricity might be considered as generation of electricity, meaning that construction of such projects of more than 1 MW connected to public grid requires a permission issued by the Minister for Infrastructure. Apart from the aforementioned permission required at a very low threshold, the status of such projects with respect to charging is also uncertain. When taking electricity from the public grid they could be treated as end users in this respect, despite the fact of returning the electricity to the grid at a later stage.

5. What are the main entities in the electricity sector and what are their roles or expected roles in realation to energy storage?

The Ministry of Infrastructure, Directorate for Energy, is the Government body responsible for Slovenian energy policy. It is supported by the Energy Agency (“EA”) as the regulatory authority supervising and regulating the field of electricity thereby executing the regulatory framework in Slovenia. 

SODO is a 100% state owned limited liability company and performs the tasks of the Distribution System Operator (“DSO”) as a public utility service. It is mainly responsible for providing distribution services, the maintenance and development of the distribution network, guaranteeing long term capacity demands and the security of the network, ensuring non-discriminatory treatment of network users, providing relevant data to potential network users and anticipating network usage and adjusting capacities.

There are five regional companies which own the distribution network infrastructure and are sub-contracted to provide distribution services for SODO: Elektro Celje, Elektro Gorenjska, Elektro Ljubljana, Elektro Maribor and Elektro Primorska. Subject to the Third Energy Package requirements, the regional distribution companies were obliged to unbundle their distribution and supply activities. Despite the unbundling of electricity supply activities from distribution, these companies are majority-state owned and remain under effective state control. If an electricity storage operator decides to access the distribution network, it must enter into contracts with SODO and/or the sub-contracted distribution companies. 

Finally, ELES, a 100% state-owned limited liability company, is the Transmission System Operator (“TSO”) and owns the 400w and 220 kV transmission networks as well as the majority of the 110 kV network. Parties (including entities engaged in storage of electricity) must enter into a contract with the TSO before they are given access to the transmission network (for example direct supply to large industrial users etc.).