NEMS Activities
As the Power System Operator, we work with the various market participants to ensure compliance with various operational standards and obligations. These are done through facility registration, dispatch instructions compliance monitoring, adequacy and security assessments and dispute management.
Agreements with Market Participants
Market Participants in the National Electricity Market of Singapore as well as Generation Licencees are required to enter into contractual agreements with the Power System Operator.
- Power System Operator-Market Participant Agreement
This agreement serves to establish a contractual relationship between the PSO and each market participant who wishes to trade in the NEMS and enable the parties to enforce obligations under the market rules. - Generation Facility Operating Agreement
This agreement will establish the contractual relationship between the PSO and the Generation Licensee to allow the PSO to dispatch Generation Licensee's Generation Facility(ies).
Facility Registration
Every Market Participant is required to provide up-to-date data of its generation or interruptible load facilities to the Power System Operator. These technical data define and represent the physical characteristics, ratings and operational limits of all relevant equipment/facilities connected to the PSO-controlled system and are required by the PSO to:
- Assess the security and reliability of the power system
- Direct operations of the transmission equipment
- Dispatch the registered generation and load facilities
- Assist the Energy Market Company with registration of the MP’s facility; and
- Provide up-to-date data to the EMC for market clearing purpose.
The timely submission of accurate and complete data is critical to participation in the NEMS, real-time operation of the power system, outage planning, stability and security assessment applications for the power system model that uses these data.
Relevant registration forms can be downloaded from the EMC website.
> Back to TopDispatch Data to EMC
Details of power system information such as the network status, outage schedules and load forecasts that are sent to Energy Market Company, the market operator, are described here.
EMS Network Status
The National Electricity Market of Singapore (NEMS) Market Clearing application requires the most recent network status and measurements data from PSOD’s Electricity Management System. The network status file is produced once prior to each trading period.
EMS Outage Schedule
The Outage Schedule files covers all planned network outage schedules for the current day and the following seven days. They are produced at least once per day.
If a change were made to the planned network outage for the current day or the following day, a new set of Outage Schedule interface files would be produced and sent to the NEM.
EMS Load Forecasts
The EMS system sends short-term load forecast (STLF) and very short-term load forecast (VSTLF) data to the NEMS.
The VSTLF forecasts load by trading period for up to three hours ahead and is generated once per trading period. The short-term load forecast (STLF) forecasts load by trading period for up to 14 days and is generated once per day.
> Back to TopDispatch Schedules from EMC
The Power System Operation Division (PSOD), received the generation dispatch schedules produced by the Energy Market Company and assess its feasibility before dispatching the generators accordingly.
Market Dispatch Instructions
The National Electricity Market of Singapore (NEMS) produces dispatch schedules, prior to each trading period. These are deemed to be dispatch instructions unless override by PSO
Dispatch instructions include energy, regulation and reserve schedule for each generation/load facilities.
Market Short-Term Pre-Dispatch, Market Pre-Dispatch and Market Outlook Schedules
The Market Clearing application also produces short-term pre-dispatch, pre-dispatch and market outlook schedules as defined by the Market Rules. These schedules, provide PSO with medium and long view of operational feasibility of the dispatch schedules.
> Back to TopElectricity Market Compliance Monitoring
The Power System Operator provides every non-compliance notice issued to the Market Surveillance and Compliance Panel via the Market Assessment Unit of the Energy Market Company.
A non-compliance notice can be issued to the relevant Market Participant on either an event of non-compliance with the PSO's directions, dispatch instructions or a breach of the Market Rules especially with regard to operation of the PSO-controlled system.
> Back to TopAncillary Services
Ancillary services mainly deal with balancing of power supply and demand over short time intervals throughout the power system. These services, regulation and reserves, are essential for the secure operation of the power system and ensuring that electricity supplies in Singapore are of acceptable quality.
In addition, Contracted ancillary services that may be procured for secure operation of the power system, these are:
- Reactive support and voltage control service
- Black-start capability
- Fast-start services
- Reliable must-run services
Currently, only Black-Start services are required.
The ancillary services may be called upon by the Power System Operator to maintain security and reliability of the power system.
A sample of “Ancillary Services Contract Agreement" can be downloaded from the Energy Market Company website.
> Back to TopOutage Co-ordination
The Power System Operator is responsible for the coordination of maintenance schedule of registered generation facilities, generating stations and transmission facilities as well as the release of these facilities for construction, testing, commissioning and repair purposes.
The PSO coordinates the outages so as to ensure sufficient generating units and adequate transmission network capacity to meet forecasted demand, operating reserves and secure operation of the transmission system
> Back to TopPower System Adequacy & Security Assessment
The Power System Operator assesses the adequacy and security of the PSO-controlled system on daily and monthly basis and prepares the Adequacy and Security Assessment (ASA) over the following two time frames:
- Monthly assessments, covering a 12-month period commencing from the following month; and
- Daily assessments, covering a 14-day period beginning at the end of the current day.
These adequacy and security assessments are essentially used to identify periods where there may be inadequate generation/ transmission capacity to cater for expected load, or security-related events on the PSO-controlled system that may require actions to be taken by market participants or the PSO.
> Back to TopRepresentations (Dispute Management, TWG, RCP, URMC)
The PSO is represented in various NEMS committees and panels as described below.
Dispute Management
A comprehensive but flexible dispute resolution procedure that covers all Market Participants, the Market Support Services Licensee (MSSL), Energy Market Company and Power System Operator is set out in the Market Rules.
Technical Working Group (TWG)
The Technical Working Group (TWG) reports to the Rules Change Panel (RCP) and is responsible for examining the on-going evolution of the dispatch and price discovery process, balancing economic, financial and technical considerations in creating a more efficient wholesale electricity market.
Rules Change Panel (RCP)
All proposed modifications to the Market Rules are reviewed by the Rules Change Panel (RCP). Thereafter, the RCP makes a recommendation to the EMC Board and the Rules Change endorsed by the EMC Board is submitted to Energy Market Authority for approval.
Urgent Rules Modification Committee (URMC)
Urgent modifications by this committee will apply for no longer than a period of one year. During this period, the EMC has to submit the urgent modification to the rules change panel for its consideration via the usual rules change approval processes.
> Back to Top