This RP focuses on three main aspects of grid-connected energy storage: safety, operation and performance. These aspects are assessed for electricity storage systems in general, i.e. a technology agnostic approach). Furthermore, recommendations applying only to specific energy storage technologies are provided wherever necessary.

The RP concerns electrical energy storage systems and technologies. The energy going into and out of these systems is electrical energy (electricity), whereas the energy stored in the storage medium may have different forms (see Sec.2). Explicitly out of scope is chemical and thermal energy storage, such as hydrogen storage or heat storage. Electric vehicles are not currently considered to be grid-connected storage and are not considered within scope. With respect to the application types of energy storage systems, only home storage systems are not considered within scope given their distinctly different nature. All electricity storage applications at the high, medium and low voltage grid level as well as industrial behind-the-meter storage and storage in microgrids and island grids are considered within scope.

The proposed guidelines are limited to common requirements, based on worldwide accepted regulation and best practices like IEC, ISO and IEEE standards. Applying this RP will not guarantee a fully secure storage system: new technology will always invalidate previous designs and safe components will not automatically result in a safe system.