The recent multi-day blackouts in Panay that were caused by multiple trip offs or shutdowns of various power plants in the island, including PEDC Units 1 and 2 (83 megawatts each), and the 135MW PCPC. The loss of the 3 largest power generating units, along with the planned maintenance shutdown of the 150MW PEDC Unit 3, 451MW of the total 656MW of power generated within the island was lost, and of course the grid collapsed.
There are two major causes of the extended blackouts that ushered in the new year for Panay.
The first is that when a power plant goes offline or shuts down, it cannot just be restarted like a stalled car after you let go of the clutch too early. The power plant operators cannot simply turn a key or push a button that will turn it back on within seconds or minutes. It takes hours, if not days, to restart a stalled power plant and that was why it took so long for the grid to be stabilized.
The second major reason for the days-long blackouts is that the Panay grid apparently lacked the connections to import power from outside the island in order to stabilize it. So, even if the missing 300ish MW were available from other power plants in other parts of the country, there was still no way to transmit that power to Panay without endangering the stability of the grid of other islands, like its neighbor, Negros.
So what happened was that the island fell into a state of rolling blackouts, as the grid operator and distribution utilities tried to make do with whatever power was available, both from within the island, and from the transmission lines from other islands could supply. Rolling blackouts are the only possible solution during a severe power shortage because the remaining power available simply cannot be shared by everyone as our grids need the proper voltage to operate properly. What happens is the available power is directed to parts of the grid for a certain period of time, and then, to be fair to those that had no power, the available power is shuffled around among the different areas of the grid and distribution network.
The National Grid Corp. of the Philippines has been getting the brunt of the blame for the blackouts because had the grid been more robust, the blackouts would’ve been avoided. However, it must be noted that the NGCP only transmits the power, but doesn’t generate it, so when a massive chunk of the power it is supposed to deliver suddenly disappears, then you can’t really blame them for the blackouts, right?
Another question that often pops up during blackouts is the surplus of renewable energy from the country’s RE capital of Negros Occidental. If there is so much RE, then why are we still getting massive blackouts?
The thing about RE is that it is variable in nature, especially solar, or PV, which can experience wild variations in the power it generates, depending on the cloud cover, so it is not very stable. Also, it does not work during night time, which is when a blackout is most felt. That is why energy officials kept talking about more baseload capacity, which while aren’t mostly RE, are not variable sources of power.
Another thing about power in an archipelago like the Philippines is that it has to be transmitted across great distances and over/under seas. Even if we had a surplus of power somewhere else, if the grid connections to Panay couldn’t handle the imported power, that extra or reserve power would still be undeliverable. This is where the NGCP is taking a lot of heat, because as the grid operator, its mandate is to make sure that the country’s power supply being provided by power plants from different parts of the country is shareable to all parts of the country, especially in major islands like Panay and Negros. The multi-day blackout in Panay simply proves that if the power generators that are outside of NGCP’s control fail, the NGCP grid infrastructure still wasn’t robust enough to handle such failures and deliver whatever reserve or surplus power is available to where it is badly needed.
Maybe the NGCP wasn’t ready to transmit any surplus power because it knows there is none available anyway. After all, if you come to think of it, even if transmission capacity was available, where was Panay’s missing 300MW going to come from in this country that seems to be in a constant state of power shortage?
What has become obvious after Panay’s woes is that our national grid and power supply is still in a precarious state, where one failure has the potential to lead to days-long blackouts. NGCP has to step up and upgrade the grid’s robustness, while the power sector also has to make sure there is always enough reserve capacity available, either in baseload form, or through quick reaction reserve power plants that are smaller but can respond to such situations within minutes instead of days. For this to happen, the NGCP, power producers, and Department of Energy will have to work together to upgrade our power grid and make it able to withstand situations such as the one that happened in Panay at the start of the year.*