What a battery can sell
What ancillary services can a battery sell in National Electricity Market of Singapore (NEMS)?
National Electricity Market of Singapore (NEMS) has 6 ancillary-service products, across 6 families — regulation, frequency containment, contingency reserve, reactive power & voltage, black start & restoration and other services: Black Start, Contingency Reserve, Fast Start Ancillary Service, Primary Reserve, Reactive Support and Voltage Control, Regulation. Response timing, direction and eligibility for each are in the cards below, as the official sources state them.
Facts below are stated as the official sources state them. A missing line means the
source does not state that value — never that the value is zero.
Regulation
-
Regulation REG
operational
Correct continuous supply-demand imbalance and maintain system frequency through AGC-capable movement.
- Direction
- raise; lower
- Full activation
- 60 s
- Trigger / range
- PSO AGC instruction; no fixed public Hz threshold.
- Eligibility
- Registered AGC-capable facilities satisfying telemetry and performance standards.
- Typical procurement
- PSO requirement varies by system conditions; no stable range in Appendix 5A.
Appendix 5A specifies maximum 60 seconds for full offered regulation capacity; it does not specify one separate sustain duration.
Frequency containment
-
Primary Reserve 9-second reserve
operational
Automatically arrest frequency decline after a contingency.
- Direction
- raise generation; lower load
- Full activation
- 9 s
- Sustain
- at least 10 min
- Trigger / range
- Automatic response to a contingency/frequency excursion; facility technical settings apply.
- Eligibility
- Registered facilities passing primary-reserve performance requirements.
- Typical procurement
- System requirement is dynamic; an EMA illustration of roughly 600 MW is not treated as a fixed rule requirement.
Scheduled MW response must be automatic within 9 seconds and maintained until 10 minutes from the trigger. The 600-second field records the rule's total response-duration convention from trigger, not an additional hold after full activation.
Black start & restoration