44 ieee power & energy magazine september/october 2021 1 2 Directed ESSs/Self-Provision $ Greater Variability and Uncertainty Key NEM Reform $ $ $ $ Inverters Replacing Synchronous Generators ` $ Inertia NEM 2022-2023 $ Inertia $ WEM 2022 NEM 2025+ Inertia Market = Status Quo (Service Not Remunerated) = Status Quo (Service Remunerated) = = Long-Term Ambition Potential Future Remunerated Design $ FCAS $ FCAS w/FastFrequency Response* NEM 2023 NEM 2025+ $ Frequency Response Demand Curve $ Operating Reserves Mandatory Primary Frequency Response NEM 2022 $ Structured Procurement of ESSs NEM 2022-2024 3 Spot Market-Based ESSs $ Operating Reserves Demand Curve Mandatory Primary Frequency Response $ Contingency Reserve WEM 2022 $ WEM 2022 Regulation Regulation $ $ Contingency Reserve $ System Strength WEM + NEM 2022-2023 $ System Strength System Strength Coordinated Through Ahead Markets and Scheduling to Replace Ad-Hoc Directions Innovative Design? $ System Strength Demand Curve Future Co-Optimization figure 8. A possible road map for ESSs in Australia (the NEM and WEM) to 2025 and beyond, indicating an evolution toward spot market-based mechanisms, where possible. (Source: adapted from FTI Consulting's 2020 Report to the ESB.)