The Energy Regulatory Commission (ERC) approved on 12 March 2012 a Resolution setting the installed generating capacity and market share limitations (MSL) for 2012. The Resolution was issued to reflect the changes in the installed generating capacity per grid and in the national grid as determined by the ERC in 2011 brought about by the inclusion of and increase in the capacity of some plants and deactivation, retirement or shutdown of some others for various reasons.
A grid refers to the high voltage backbone system of interconnected transmission lines, substations and related facilities. There are three grids which form the national grid, namely: (1) Luzon Grid; (2) Visayas Grid; and Mindanao Grid.
The 2012 and 2011 installed generating capacity and the MSL per grid and the national grid are as follows:
| Grid | As of March 2011 Installed Generating Capacity (kW) | As of March 2012 Installed Generating Capacity (kW) | % MSL per RA 9136 | As of March 2011 Installed Generating Capacity Limit (kW) | As of March 2012 Installed Generating Capacity Limit (kW) |
| Luzon | 11,167,476.01 | 11,387,583.53 | 30% | 3,350,242.80 | 3,416,275.06 |
| Visayas | 2,051,956.00 | 2,063,199.00 | 30% | 615,586.80 | 618,959.70 |
| Mindanao | 1,756,583.00 | 1,768,848.00 | 30% | 526,974.90 | 530,654.40 |
| National | 14,976,015.01 | 15,219,630.53 | 25% | 3,744,003.75 | 3,804,907.63 |
Section 45 (a) of the Electric Power Industry Reform Act (EPIRA), in part, states that "no company or related group can own, operate or control more than thirty percent (30%) of the installed generating capacity of a grid and/or twenty-five percent (25%) of the national installed generating capacity.” This is to safeguard electricity end-users against harmful monopoly and market power abuse. The ERC determines the installed generating capacity per grid and in the national grid as well as the MSL on the 15th day of March of each year or as often as necessary, based on the maximum capacity of the power plants.
To properly set the market share limitations, the ERC promulgated the "Guidelines for the Determination of Installed Generating Capacity in a Grid and the National Installed Generating Capacity and Enforcement of the Limits on Concentration of Ownership, Operation or Control of Installed Generating Capacity Under Section 45 of Republic Act No. 9136.” Article II, Section 5 of the Guidelines excludes PSALM or NPC from observing the MSL during the time that its assets are being privatized. This holds true for isolated grids not connected to the high voltage transmission system.
"The ERC will remain steadfast in safeguarding stakeholders, particularly the electricity consumers, from unfair competition and market abuse. Rest assured that your regulator will strictly monitor player in the generation sector to ensure their compliance to rules and regulations,” ERC Chairperson and CEO Zenaida G. Cruz-Ducut said.
