This policy brief is based on the workshop titled “ Beyond Batteries – Exploring Long-Duration Electricity Storage Solutions ” co-organized by the British Embassy Budapest and REKK, which took place on January 29^th, 2025.

Main conclusions:

• Long-duration electricity storage (LDES) technologies can further support the integration of intermittent renewables, contribute to grid stability, support large-scale electrification and the decarbonisation of hard-to-abate sectors through sector coupling.
• Several long-duration (minimum 6 hours) and seasonal storage solutions exist with different technological characteristics and applications. The UK has been at the forefront of LDES innovation, with researchers, innovators, and technology providers already piloting these technologies.
• The UK and Hungarian revenue compensation schemes differ and have their advantages and challenges. The choice of method is likely to depend on many factors (e.g. market environment, the purpose of the support). As there is currently no practical experience with either approach, their success can only be evaluated in the future.
• Regulation should encourage market players to take advantage of the flexibility offered by storage and facilitate accelerated and simplified connections for stand-alone storage units or those installed alongside distributed generation units. Furthermore, long-term tariff regulation tailored to storage characteristics is also required to support the wider adoption of LDES and electricity storage in general.
• LDES is considered as one of the many solutions that can support future decarbonisation goals. Analyses show that over the next two and a half decades, several hundred GW of LDES capacity will need to be commissioned. Future support schemes can help accelerate the deployment of LDES as their levelized cost continues to decrease.