Dear Colleagues,

Energy storage is expected to play a key role in enabling the future grand transitioning of the global electricity sector to a carbon-free, reliable and secure electricity system, facilitating the grid penetration and market introduction of renewable-based power generation.

Currently, there is limited energy storage capacity worldwide. Most applications are pumped hydro storage plants, while other forms, such as electrochemical storage, constitute a small slice of the pie, but they are developing at a fast pace, taking advantage of their falling capital costs. According to the latest estimates, it is expected that when moving towards a fully renewable system, significant storage capacity will be necessary to cope with the variable nature of renewables and to provide the system with the required levels of flexibility and capacity, in order to safeguard the security of energy supply.

In the medium term, it is expected that a large share of the required levels of flexibility will still be provided by conventional power plants and electricity trading between different countries, while the remaining share will be satisfied through pumped hydro storage and batteries. On a longer-term basis, taking advantage of the expected declining capital costs of electrolysis, large volumes of “decarbonized” hydrogen (produced with the use of electricity coming from renewables) will need to be stored in storage facilities (e.g. in underground geological formations), in order to handle and recover the increasing surplus of renewable production, as also to manage deficit situations related with the very high share of non-controllable renewables in the generation mix.

This Special Issue invites high-quality research papers covering a wide range of topics related to the key challenges of well advanced or forthcoming grid-scale energy storage applications from the aspect of a number of underlying technical, economic and regulatory issues that need to be overcome to allow further storage deployment at European and global level.

Prof. Dr. John Anagnostopoulos
Dr. Marina Kapsali
Guest Editors

Manuscript Submission Information

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• Electricity system
• Electricity production and storage
• Grid-scale storage
• Electricity system flexibility
• Security of energy supply
• Renewable energy sources
• Decarbonization
• Carbon-free electricity
• Energy storage technologies
• Pumped hydro storage
• Batteries
• Hydrogen storage
• Energy storage applications
• New storage technologies