IEC TR 62786-101:2026 ED1

Distributed energy resources connection with the grid - Part 101: Gravity storage connection to the grid

Scope

IEC TR 62786-101:2026 provides the principles and general technical characteristics of gravity energy storage systems (GESS) connected to the distribution network. It provides a reference for the planning, design, grid connection and operation of GESS. It includes an introduction to GESS, grid-connection methods, grid-connected characteristics, grid-connected operation and grid-connected testing and so on.
GESS can use liquid or solid mediums for storing or releasing energy. For example, traditional pumped storage utilizes liquid water to achieve energy storing or releasing. This document only focuses on the solid GESS, which utilize solid materials (such as concrete, slag, construction waste, etc.) for energy storage. Generally, GESS can be classified as vertical GESS and slope GESS. In the GESS, the motor-generators (MG) that are directly connected, or indirectly connected to the low voltage (LV) or medium voltage (MV) distribution network through converters, transfer the energy between the mass blocks and the grid. This document reports the grid-connection method, active power response characteristic, response of active power to frequency, response of reactive power to voltage and test of direct grid connection through synchronous motor-generator (SMG), as a supplement to IEC TS 62786-1:2023.
This document describes the interface arrangement for the connection of GESS to distribution networks with the nominal frequency of 50 Hz or 60 Hz.