New FCAS resources dominate enabled levels in 2024

Using the latest GSD – GSD2024 – we take the opportunity to reflect on which resources are providing FCAS services: How much, and how it is changing?

Paul’s Focused stats for units participating in FCAS in the GSD2024 spurred me to update one of the charts WattClarity produced for an article last year.

FCAS enablement grouped by new and traditional resource types

The chart captures the monthly enablement levels (represented as GWh) for each of the 10 FCAS services in the NEM.  We chart the total in grey, and two lines represent the split between new and traditional resources.

Traditional resources are the thermal generating units and hydro units (pumps and generation). The new resources represents largely inverter-based resources such as grid-scale batteries. It also includes smaller contributions from wind and solar units (where participating) and the newer ancillary service units (such as VPPs).

Last year we had seen the rapid growth in enablement levels of the new resources. It was outpacing traditional resources in all contingency categories. Traditional resources were still slightly ahead in Regulation FCAS.

A year on, to the end of 2024

A year on, to the end of 2024, with the updated chart below, we can see:

• The gap between traditional and new providers of contingency services has only widened – new resources are dominating.
  • Is this driving prices down? That’ll have to be a separate investigation.
• Provision of Regulation FCAS by traditional resources saw a decline late in 2023.
  • This was driven principally by reduced enablement levels in the Coal fleet.
  • This was resisted by steady levels of enablement in the hydro sector.
• Enabled levels in the Raise 1s market have grown since market start.
  • This is associated with raised caps as participation increases, as observed in Very fast FCAS, 2024 in review.

Each panel distinguishes the direction of the service (raise and lower) and the speed or nature of the service. Contingency services are the 1s (second), 6s, 60s and 5m (minute) services. Regulation services are denoted “Reg”.

GSD2024 holds the detail

Further information on the FCAS pages of GSD2024 is available at:

Focused stats for units participating in FCAS in the GSD2024