Reserve Market and Electricity Derivatives (WESM)
The Reserve Market is a co-optimized ancillary service mechanism within the Wholesale Electricity Spot Market (WESM) that schedules and prices contingency reserves alongside energy dispatch. It ensures the power system can respond to sudden generation shortfalls or transmission outages without compromising grid frequency and voltage stability [PEP 2023-2050 Vol. II, pp.97–98, 2023].
Rationale
The energy-only WESM structure does not price the grid’s need for standby capacity. Without a Reserve Market, the System Operator (SO ) must direct reserve provision through administrative means — neither transparent nor competitively priced. A co-optimized Reserve Market allows the least-cost provider — including batteries (Battery Energy Storage Systems (BESS) and Energy Storage System Policy ) and quick-start peaking plants — to compete for reserve procurement, improving system security and reducing overall cost [PEP 2023-2050 Vol. II, p.97, 2023].
DC2021-03-0009 Framework
DC2021-03-0009 (“Adopting A General Framework Governing the Operationalization of the Reserve Market in the WESM”) defines the Reserve Market structure. Salient features [PDP 2023-2050, Ch.3 Sec.5.2, pp.117–118, 2025]:
- Co-optimization of energy and reserves — protocols for offer submission, dispatch scheduling, and simultaneous clearing
- Operational cap, locational reserve sharing, and scarcity hierarchy for reserves
- Tradeable AS categories with minimum technical specifications and required levels
- Criteria for market/system readiness and responsibilities of power industry participants
- Pricing, billing, settlement, mitigating measures, and consumer protection cost-recovery mechanisms
DC2021-03-0009 also established supplemental policies on AS accreditation of third-party testing entities and competitive selection for the SO’s AS procurement contracts. The specific CSP procedure was subsequently prescribed by DC2021-10-0031 — see Ancillary Services (AS) for the contract procurement channel.
Reserve Categories and Required Levels (Initial Phase)
Three AS categories are tradeable in the WESM Reserve Market during the initial phase [DC2021-03-0009, §4.1, 2021-03]:
| Category | Description | Required Level (per dispatch interval) |
|---|---|---|
| Contingency Reserves | Synchronized generation capacity to cover loss/failure of the largest online generating unit or transmission element | Capacity of the largest online unit in the dispatch interval |
| Regulating Reserves | Dispatchable capacity allocated exclusively to correct frequency deviations from unpredicted demand/generation variations | 4% of total demand in the dispatch interval |
| Dispatchable Reserves | Available capacity to replenish Contingency Reserves after a unit trip or single transmission interconnection loss | Capacity of the second largest online unit in the dispatch interval |
Excluded from tradeable AS: Reactive Power Support and Black Start AS are not part of Reserve Market trading [DC2021-03-0009, §4.3, 2021-03].
The required levels must be satisfied by the SO through a combination of AS Procurement Agreements (ASPAs) and Reserve Market procurement [DC2021-03-0009, §4.5, 2021-03].
Participation and Single Buyer
SO as single buyer: The System Operator (NGCP) is the sole buyer of all AS requirements and is accountable for ensuring adequate procurement through ASPAs and the Reserve Market [DC2021-03-0009, §3.5, 2021-03].
All Generation Companies registered in WESM must offer their maximum available capacities at all times in both energy and all reserve categories for which they are certified [DC2021-03-0009, §3.1, 2021-03].
Extended participation: Embedded Generators may participate as ASPs subject to protocols under DC2019-02-0003. Load facilities (demand-side resources) may also participate as ASPs subject to ERC-approved accreditation procedures to be developed by the SO in consultation with the MO and host DUs [DC2021-03-0009, §§5.2–5.3, 2021-03].
Third-party AS testing: Allowed pending ERC guidelines for selecting and accrediting third-party testing entities [DC2021-03-0009, §6, 2021-03].
Settlement Flow
- MO nets contracted reserves from total scheduled reserve quantity and bills the spot reserve trading amount to the SO (single buyer)
- SO remits the total spot reserve trading amount to MO
- MO remits payment to ASPs for their spot reserve quantities
- SO settles contracted capacity payments to scheduled ASPs outside the market, under each ASPA [DC2021-03-0009, §§8.1–8.5, 2021-03]
Three-Year Study Mandates
The SO, MO, and WESM Governance Arm (WGA) were each directed to conduct studies within three years of issuance and submit findings to DOE/ERC, covering: (a) introduction of raise and lower reserve services; (b) reserve level requirements for frequency regulation under 5-minute dispatch; and (c) reserve offer price cap/floor calibration. The WGA was additionally tasked with benchmarking reserve offer methodologies and setting readiness criteria for the enhanced Reserve Market [DC2021-03-0009, §§9.8, 10.4, 11.4, 2021-03].
Implementation Timeline
| Milestone | Date |
|---|---|
| Trial Operations Program (TOP) directed by DOE Advisory | 26 June 2023 |
| ERC Interim Relief on PDM (ERC Case No. 2023-002 RC) | 24 August 2023 |
| DC2023-09-0026 — “Declaring Commercial Operations of Reserve Market” | September 2023 |
| Final Preparations Stage begins (non-binding parallel ops) | Post-effectivity of DC2023-09-0026 |
| WESM Governance Arm ECO to finalize ROCC/RCS guidelines | 15 November 2023 |
| AS Provider registration deadline (original target) | 26 October 2023 |
| Declared Full Commercial Operations target | 26 December 2023 |
| SO Prudential Requirements posting deadline | 25 March 2024 |
| Phase 1 actual commercial operation | 26 March 2024 |
| Phase 2 — PGC 2016 reserve classification, technical specifications, rule amendments | Medium-term (2025–2028) |
TOP results are non-binding — trial-period scheduling, dispatch, settlement, and cost recovery have no commercial effect. DC2023-09-0026 set the Full Commercial Operations target for 26 December 2023, but per PEP 2023-2050 Vol. II reporting, Phase 1 actual commercial operation was achieved on 26 March 2024 — approximately three months later than declared [DC2023-09-0026, §1.2, 2023; PEP 2023-2050 Vol. II, p.98, 2023].
Reserve Market Compliance Mechanisms (DC2023-09-0026)
Reserve Offer Capacity Compliance (ROCC) and Reserve Conformance Standards (RCS). All Trading Participants must fully comply with ROCC, RCS, and applicable WESM Rules from the Full Commercial Operations Date. The WESM Governance Arm’s Enforcement and Compliance Office (ECO) monitors compliance, imposes sanctions, and recommends rule changes — but must consider the “transitory nature” of early Reserve Market operations when evaluating non-compliance [DC2023-09-0026, §1.2.1, 2023].
SO Prudential Requirements. The System Operator (NGCP), as the single buyer of all reserves, must post Prudential Requirements per WESM Rules by March 25, 2024, and ensure timely monthly bill settlement with IEMOP [DC2023-09-0026, §1.2.2, 2023]. ERC support is required for SO’s cost recovery and settlement system changes.
Electricity Derivatives Market (EDM / Contracts for Difference)
Alongside the Reserve Market, IEMOP is studying Contracts for Difference (CfD) as a price-hedging mechanism. A CfD pays a generator the difference between a contracted “strike price” and the prevailing spot price, protecting project revenue from market volatility and providing investment certainty for new capacity [PEP 2023-2050 Vol. II, pp.97–98, 2023].
UK model (reference): UK CfD introduced October 2014; supports RE projects over 5 MW with a two-way payment — the generator receives top-up when spot is below the strike price; pays back the difference when spot is above it.
Philippine legal barrier: Only banks and insurance companies are currently authorized to deal in over-the-counter derivatives; only equity, interest rate, and currency derivatives are actively traded. The PEMC completed a market study (2020) finding significant legal/regulatory barriers. IEMOP’s ongoing study targets medium-term (2025–2028) implementation [PEP 2023-2050 Vol. II, p.98, 2023].
Capacity Market
The DOE has proposed an Independent Impact Assessment of a Philippines Capacity Market — a mechanism to signal and incentivize adequate long-term generation investment beyond the energy and reserve markets. No implementation timeline has been established as of 2023 [PEP 2023-2050 Vol. II, p.98, 2023].
A functioning Capacity Market would address structural concerns about generation adequacy under high-VRE penetration scenarios (CES-1 and CES-2), where the energy market alone may not send sufficient price signals for new dispatchable capacity investment.