The European Union has introduced new regulations requiring all newly built or significantly upgraded energy storage and renewable energy projects above 1MW to possess Grid-Forming capabilities. This represents a major transition from passive grid connection to active participation in maintaining Grid Stability. These systems will operate similarly to synchronous generators by autonomously regulating voltage and frequency, helping to ensure a reliable and resilient power system as renewable penetration continues to grow.

According to the Phase II technical report released by ENTSO-E, grid-forming energy storage systems must meet several essential technical requirements. They must maintain voltage stability during frequency or phase fluctuations, provide rapid reactive current, and remain synchronized without external references. In terms of performance, the systems are required to achieve response times of less than 10 milliseconds and a power oscillation damping rate of at least 5%. In addition, they must supply millisecond-level Synthetic Inertia, comparable to a virtual synchronous machine, to effectively support frequency control and minimize the impact of sudden grid disturbances.

These systems also need to pass strict disturbance tolerance tests, including voltage dips, step changes, and phase angle jumps, to confirm stable operation under challenging conditions.

The NC RfG 2.0 regulation is expected to be finalized in 2026, by a typical transition period of around three years. Consequently, most projects will need to comply fully by 2028–2029. Developers should therefore begin upgrading control systems, PCS technology, and testing solutions to ensure readiness and long-term compliance.