Transmission firm National Grid Corporation of the Philippines (NGCP) forthrightly stated that it is amenable to the ‘audit call’ by the Department of Energy (DOE), granted that these are carried out within the legal bounds of its concession agreement with the government as well as its franchise issued by Congress. In a press briefing, NGCP Assistant Vice President and Head of Corporate Communications Cynthia P. Alabanza indicated that through the years, "We’ve been subjected to numerous audits, and so long as it’s within the regulatory framework that governs us, we are open.” She specified the company is similarly “open to inspection and audit by different government agencies, for so long as covered by regulatory framework and within the NGCP franchise and the concession agreement and other applicable rules and regulations.” Following series of transmission line tripping incidents that flipped Luzon and Visayas grids into  rotational blackouts, Energy Secretary Raphael P. M. Lotilla apprised media early this week that the government will be undertaking follow-through performance audits on the regulatory as well as contractual compliance of the transmission firm. On the recent glitches in the power system that led to service interruptions, NGCP argued that “the system disturbance and the widespread outages in Panay Island between 27 and 29 April, and the red alert raised in the Luzon grid resulted from a confluence of events that support its call for better and proper power system planning across all three (3) members of the energy supply chain: generation, transmission and distribution.” The company emphasized “while there were grid incidents monitored in both the Luzon red alert on May 8, as well as the Panay Island outages, these incidents by themselves, ought not to have caused the effects seen.” The transmission firm expounded “in the case of Panay Island, NGCP’s protection systems, which were communicated and coordinated with its grid-connected customers from both the generation and distribution sides, functioned as intended.” On its assessment, NGCP opined that “only the consumers connected to the line that tripped should have been disengaged from the grid,” qualifying though that “it was unfortunate that a power plant disengaged from the transmission system unexpectedly.” The power generating facility was not named by the transmission firm, but it referred to it as a major plant that has 135-megawatt capacity. And in the Visayas grid, that has been classified as the 135MW coal-fired power plant of Palm Concepcion Power Corporation. NGCP noted this response from the generating unit was both "unexpected and undesirable." It added that the "resulting undervoltage and underfrequency was severe and unrecoverable, and was the direct cause of the tripping of other power plants connected to the system, and ultimately, the Panay sub-grid collapse.” The transmission firm narrated that the subsequent rotational blackouts on April 28 and 29 had been linked to the April 27 technical glitches in the system. On the May 8 Luzon power interruptions triggered by the tripping of its Bolo-Masinloc 230-kilovolt line, NGCP  conveyed that “the load carried by Line 2 when it tripped was automatically transferred to Line 1,” adding that “each of lines 1 or 2 is more than capable to singularly carry the entire loading of the Bolo-Masinloc 230kV facility at any time.” NGCP thus claimed that the system malfunction “should have ended there,” but “there was an unexpected and undesired response from a generating plant which tipped the balance of supply and demand, and a red alert was raised.” In the sequence of events previously presented by the DOE to the media, it was the line tripping at the Bolo-Masinloc line that happened first; before the Masinloc plant was plunged into a forced outage. On the delayed transmission projects of the company, Alabanza had given assurance of their completion dates by July to August this year as committed by NGCP President Anthony Almeda to the energy department. “NGCP commits to complete several large transmission projects within the next few months to help strengthen the transmission system and better support the power system,” the company reiterated.