System Constraints

GSO will normally dispatch the lowest-cost generation to meet system demand. A system constraint is applied in the Grid operation’s generation dispatch when the unconstrained dispatch does not allow GSO’s operation to meet the TSRS(Transmission System Reliability Standards)’s Performance Criteria and Limits. For example, system constraint shall be applied to generation dispatch under conditions whereby transmission assets are expected to be operated above their thermal capacity limits under basecase condition or under any defined contingency event. GSO shall conduct appropriate system studies and publish system constraints which may be applied under:

Existing Constraint – when the Grid system are all intact without major impacting system outages but due to inherent Grid system shortcomings, lowest-cost generation dispatch may not be possible and may result in unsecure system operation. Existing Constraint shall be published until Grid system shortcomings are lifted.

Constraints Due to Outage – conditions when the Grid system has to deal with an outage situation when some assets are not available. Constraints Due to Outage shall be published as an information seven days ahead until the outage is normalised.

Regional Generation Availability

Generation Clusters are defined as the composition of major generators with distinctive generation-transmission operation boundaries.

Northern Generation Cluster is composed by PLPS, GLGR, SKSP, NPRI, SGRI, SGB3, JMJG, JMJG4, MJG5, BSIA, TMGR, KNRG, LPIA, UPIA, CEND, UJLI, SYPS and SIHY generators.

Eastern Generation Cluster is composed by PGAU, HTRG, KNYR and YTL PAKA generators.

Southern Generation Cluster is JMHE, TJPS, PGLA, TBIN, TBIN4, PGPS, PCGP and SPGP generators.

Central Generation Cluster is composed by PKLG, CBSB, PJPS, KLPP and JMAH generators.