ERC approves reclassified power reserve categories

Posted on November 02, 2016
http://www.bworldonline.com/content.php?section=Economy&title=erc-approves-reclassified-power-reserve-categories&id=135753

THE Energy Regulatory Commission (ERC) has approved the final draft of the 2016 edition of the Philippine Grid Code, which enumerated several changes including a new classification for electricity reserves.

The code sets the basic, requirements, procedures and standards that govern the operation, maintenance and development of the high-voltage backbone transmission system of the Philippines.

Under the new code, the classification of reserves has been changed from contingency reserve, regulating reserve and dispatchable reserve into primary reserve, secondary reserve and tertiary reserve, respectively.

“The reason being is to set hierarchy of deployment of reserves for specific events,” it read.

In the past, contingency reserve is allocated to immediately answer any reduction of supply due to loss of the largest generating unit online. Regulating reserve is the operating requirement to maintain a balance of available capacity and the system demand due to small variations during normal operation. Dispatchable reserve is readily available for dispatch to replenish contingency reserve.

These reserves are support or “ancillary” services that are necessary to support the transmission capacity and energy that are essential in maintaining power quality and reliability of the grid.

Primary reserve is a mandatory ancillary service to be delivered by each power generating unit operating under the “governor control” mode -- or the unit’s unblocked turbine speed -- to replace the capacity lost during contingent events.

Under the new code, a yellow alert notice is issued by the system operator when the primary reserve is less than the capacity of the largest synchronized power generating unit or power import from a single interconnection, whichever is higher.

A red alert notice is issued by the system operator when the primary reserve is zero, a generation deficiency exists, or there is critical loading or imminent overloading of transmission lines or equipment. A red alert warning is issued by the system operator to users regarding a planned demand reduction following the declaration of a red alert.

Secondary reserve is required from certified generating units providing ancillary services.

Among others, tertiary reserve is used by the system operator to replenish the secondary reserve. The system operator can also use tertiary reserve in cases of unplanned tripping of a generating unit or a transmission line, which creates a generation-loan imbalance. -- Victor V. Saulon