IEC TR 62786-102:2025 PDF

Overview

IEC TR 62786-102:2025 - Distributed energy resources connection with the grid, Part 102: CAES connection to the grid - defines principles and technical needs for interconnecting compressed air energy storage (CAES) systems to distribution networks. Intended as a practical companion to IEC TS 62786-1:2023, this Technical Report covers planning, design, operation and testing of CAES interconnection for networks operating at 50 Hz or 60 Hz. It addresses the unique interface, control and test requirements that ensure safe, reliable grid integration of CAES as a distributed energy resource (DER).

Key topics and technical requirements

• Grid-connected process and connection scheme: recommended POC selection, startup/shutdown sequences for charging and discharging, and state transition management.
• Active/reactive power response characteristics: documented response of active power to frequency, current, injecting mass flow, and pressure; reactive power response to voltage. Includes characteristic curves and operating envelopes.
• Power quality and EMC: interface considerations to meet distribution network power quality and electromagnetic compatibility requirements.
• Communication, automation and controls: interoperability, telemetry and control needs to integrate CAES with distribution automation and grid operators.
• Monitoring and protection: protections, disturbance immunity and supervisory functions tailored to CAES subsystems (compressors, turbines, storage).
• Grid-connected testing needs: tests for voltage/reactive power response, power-generation control, charging/discharging timing, rated energy, and conversion efficiency.
• CAES system types and subsystems: informative annexes describe supplementary/non‑supplementary combustion CAES architectures, storage options (salt caverns, chambers, pipes), compressors, turbines and heat storage elements.

Practical applications and who uses this standard

This TR is practical for organizations involved in CAES projects and DER grid integration:

• Utility planners and distribution network operators assessing POC and interconnection requirements.
• Plant designers, CAES manufacturers and system integrators specifying control and protection schemes.
• Commissioning and test laboratories performing grid‑connected validation and performance tests.
• Regulators and grid-code authors defining performance and safety requirements for storage assets.
• Engineering consultants evaluating CAES for grid services (frequency response, peak shaving, renewable firming).

Related standards

• IEC TS 62786-1:2023 - Baseline technical specification for distributed energy resources connection; this TR acts as a supplement specific to CAES.
• IEC series on DER interconnection and grid codes (see IEC catalogue for latest editions).

Keywords: IEC TR 62786-102:2025, CAES, compressed air energy storage, grid connection, distribution network, DER, point of connection, power quality, EMC, reactive power, active power response, grid-connected testing.