New Zealand. Status: operational.
Wholesale design: Centralised pool with generator offers, purchaser bids, nodal scheduling/pricing/dispatch and half-hour final spot prices. Financial hedges are traded separately.
Energy in New Zealand Electricity Market (NZEM) trades in 2 layers: spot energy and hedge contracts.
New Zealand Electricity Market (NZEM) has 6 ancillary-service products, across 4 families — operating reserve, reactive power & voltage, black start & restoration and other services: Black Start, Fast Instantaneous Reserve, Frequency Keeping, Over-Frequency Reserve, Sustained Instantaneous Reserve, Voltage Support. Response timing, direction and eligibility for each are in the table below; a product's full record lists the official sources behind it.
Every value below comes from the official sources listed in that product's full record. Most products cite more than one, and the published sources do not say which of them states each individual value, so the binding is to the product's record rather than to a single document. A missing line means the source does not state that value — never that the value is zero.
Scroll the table sideways for the rest of the columns →
| Service | How it activates | Response | Sustained delivery | Procurement |
|---|---|---|---|---|
| Operating reserve | ||||
| Fast Instantaneous Reserve FIR raise generation; interrupt load operational | Response type post-fault automatic Trigger Contingent event; interruptible load is expected to respond within one second after frequency reaches 49.2 Hz. | Full activation 6 s | Minimum obligation at least 60 s | As stated Procured quantity is driven by the largest credible contingent event and transfer constraints for each trading period. Procured quantity is driven by the largest credible contingent event and transfer constraints for each trading period. Through co-optimised reserve clearing under scheduling, pricing and dispatch Bought half-hour clearing How it settles Final reserve price and cleared quantity by island/trading period. |
Full record for Fast Instantaneous Reserve — document bound, page for these figures not recorded What it is for Arrest frequency decline after the largest credible generating or transmission contingent event and prevent frequency falling below the security limit. In force from 11 July 2025 Who can provide it Technically approved partly-loaded or tail-water-depressed generation, storage where compliant, and interruptible load. Checkpoint recap Full activation 6 s · Minimum sustained 60 s What the source does not state The source states the full-activation requirement, a minimum delivery period, and a procurement volume in its own words. It does not state a maximum duration. Sources
| ||||
| Over-Frequency Reserve OFR lower generation operational | Response type post-fault automatic trip or reduction Trigger Contracted over-frequency relay setting; no single national threshold is stated in the procurement-plan overview. | As stated System Operator net purchase assessment; stable typical MW not published in the cited plan. System Operator net purchase assessment; stable typical MW not published in the cited plan. Through ancillary-service procurement contract Bought contract tender How it settles Contract-specific availability/service payments. | ||
Full record for Over-Frequency Reserve — document bound, page for these figures not recorded What it is for Automatically reduce generation following a frequency rise, including an HVDC-related contingent event. In force from 11 July 2025 Who can provide it Generation capable of automatic disconnection or reduction and meeting contract tests. What the source does not state The source states a procurement volume in its own words. It does not state a response time or how long delivery has to be sustained. Sources
| ||||
| Sustained Instantaneous Reserve SIR raise generation; interrupt load operational | Response type post-fault automatic Trigger Contingent event; interruptible load frequency relay settings are contract/Code specific. | Full activation 60 s | Minimum obligation at least 15 min | As stated Based on the largest credible contingent event for each island/trading period. Based on the largest credible contingent event for each island/trading period. Through co-optimised reserve clearing under scheduling, pricing and dispatch Bought half-hour clearing How it settles Final reserve price and cleared quantity by island/trading period. |
Full record for Sustained Instantaneous Reserve — document bound, page for these figures not recorded What it is for Restore and stabilise frequency after a contingent event long enough for redispatch. In force from 11 July 2025 Who can provide it Technically approved generation, storage where compliant and interruptible load. Checkpoint recap Full activation 60 s · Minimum sustained 15 min What the source does not state The source states the full-activation requirement, a minimum delivery period, and a procurement volume in its own words. It does not state a maximum duration. Sources
| ||||
| Reactive power & voltage | ||||
| Voltage Support VS reactive injection; reactive absorption operational | Response type pre- and post-fault automatic or instructed Trigger System Operator voltage requirement and contract-specific setpoints. | As stated Reactive requirement is location- and system-condition-specific, commonly expressed in MVAr rather than MW. Reactive requirement is location- and system-condition-specific, commonly expressed in MVAr rather than MW. Through ancillary-service procurement contract Bought contract tender How it settles Contract-specific. | ||
Full record for Voltage Support — document bound, page for these figures not recorded What it is for Provide reactive-power and voltage-control capability needed to keep grid voltage secure. In force from 11 July 2025 Who can provide it Contracted facilities meeting voltage-support technical requirements. What the source does not state The source states a procurement volume in its own words. It does not state a response time or how long delivery has to be sustained. Sources
| ||||
| Black start & restoration | ||||
| Black Start BS restore generation operational | Response type post-blackout manual instructed Trigger System restoration instruction. | Procurement is station-count/location based rather than a published stable MW range. Through ancillary-service procurement contract; two black-start stations are normally procured in each island Bought multi-year contract tender How it settles Contract availability/service payments; costs allocated under the Electricity Industry Participation Code. | ||
Full record for Black Start — document bound, page for these figures not recorded What it is for Start without grid supply and energise transmission assets and other generation during system restoration. In force from 11 July 2025 Who can provide it Stations passing black-start technical assessment and contract testing. What the source does not state It does not state a response time, how long delivery has to be sustained, or a standing procurement volume. Sources
| ||||
| Other services | ||||
| Frequency Keeping FK raise; lower operational | Response type pre-fault centrally instructed Trigger System Operator regulating instructions; no single fixed frequency trigger. | Minimum obligation at least 30 min | As stated Net purchase quantity is assessed separately for each island and trading period. Net purchase quantity is assessed separately for each island and trading period. Through least-cost half-hour clearing among contracted technically approved providers Bought half-hour clearing; single-provider, multiple-provider and backup arrangements How it settles Dispatched MW band paid at the provider's frequency-keeping offer price, plus applicable constrained-on/off compensation. | |
Full record for Frequency Keeping — document bound, page for these figures not recorded What it is for Manage short-term supply-demand imbalance and keep frequency at or near 50 Hz. In force from 11 July 2025 Who can provide it Technically reviewed generators or other eligible resources with an ancillary-service procurement contract. Notes from the source The current official overview describes quick variation in response to instructions but does not publish one universal full-activation time. Providers must maintain capability for the 30-minute trading period. Checkpoint recap Minimum sustained 30 min What the source does not state The source states a minimum delivery period and a procurement volume in its own words. It does not state a response time or a maximum duration. Sources
| ||||
No. New Zealand Electricity Market (NZEM)'s capacity/adequacy arrangement: No central capacity market.
none operational
Resource adequacy is supported by spot prices, contracts, instantaneous reserve and System Operator security arrangements rather than a forward capacity auction.
The 2025 ancillary-services tender was a service-contract tender for 2026-27 and not a capacity-market auction.
Frequency keeping and instantaneous reserves clear half-hourly; over-frequency reserve, voltage support and black start are procured under ancillary-service contracts.
Current as of · from the Global Electricity Market Catalogue v1.2.0 (compiled to , CC BY 4.0, rendered here with wording edited for readability). Facts belong to the linked official authorities; verify the current rules before design or bidding decisions.
The markets index holds the full set. For what the grid demands of a battery here, see the grid-code ride-through atlas.