(AmCham Taiwan|Contributing Writer: Angelica Oung) The immediate cause of Taiwan’s latest major blackout is indisputable – in fact, it was caught on camera. In a closed-caption video, the supervisor on shift at Kaohsiung’s 4,326MW Hsinta Power Plant is seen hovering in front of a control panel for 20 minutes before turning on a switch labeled 3541. The adjacent switch 3540 had had its insulation gas drained as a part of routine maintenance, which caused 3541 to short out when it was tripped. The video went dark shortly after as the power went out for almost 5.5 million users across Taiwan.
Some households in Kaohsiung, the most severely affected region, lost power for more than 12 hours. Although it is difficult to estimate the actual economic damage, the state-owned Taiwan Public Television Service quoted a figure of NT$6 billion (US$204 million). There was a human toll too, as two older men in Kaohsiung passed away after the outage caused their respiratory support equipment to fail.
The incident occurred at 9:16 a.m., when Taipower was showing a comfortable 24% in operational reserves, and electricity output from Hsinta Power Plant accounted for less than 3% of Taiwan’s grid. So then how was it possible for one user error to cause the collapse of Taiwan’s power supply in such a catastrophic manner? The authorities and experts agree: At least part of the problem lies with Taiwan’s increasingly fragile grid infrastructure.
Loss of power at Hsinta was the first of a series of unfortunate events that triggered the island-wide rolling blackout, according to Taipower’s report to the legislature following the incident. A protective relay – a component designed to trip a circuit breaker when a fault is detected – should have taken Hsinta off the grid, but ironically the new digital protective relay misinterpreted the signals from Hsinta’s older equipment, and the crisis point reached the Lunchi Ultra High Voltage (UHV) substation, near Tainan.
Even then, disaster might have been averted if the Lunchi Substation had not been undergoing major maintenance at the time. Four of Lunchi’s eight connection buses were offline, reducing the substation’s ability to separate the rest of the grid from the effects of Hsinta’s blackout. All major power stations south of Lunchi took themselves offline as a protective measure, as any “backflow” of electricity could cause significant damage to power-producing equipment.
The grid north of Lunchi was successfully isolated from the cascading collapse. But unfortunately, the Lunchi substation was the southernmost node that collected energy from the power-producing south to the power-consuming industrial north. The grids of northern and central Taiwan were forced to enter rolling blackouts because they were starved of power imports from the southern part of the grid, though they managed to recover more quickly as no power plants north of Lunchi needed to be taken offline.
Taiwan’s grid is both isolated and relentlessly centralized, with heavy reliance on larger plants like Hsinta in the south to be the workhorses that power the island. Of the more than 30 high-power voltage substations that gather and distribute power, two stand out in particular: Lunchi in the south and the Longtan UHV substation in the north, with the Zhong Liao switching station in between. Together, those three critical pieces of infrastructure form Taiwan’s electric superhighway, and traffic flows only one way: from south to north. If any of the three nodes falter, as one wrong switch flipped at the Hsinta power plant caused Lunchi to do, there is no way around this massive central artery. The result? An electrical heart attack.
“Taiwan must accelerate the development of regional smart grids that can operate both independently and in tandem with one another to improve grid resilience,” says Chiang-Chien Le Ren, professor of electrical engineering at National Cheng Kung University (NCKU). “If regions of the grid can self-isolate and protect the provision of electricity locally, we can reduce the spread and impact of future blackouts.”
The goal of a smart grid is to automatically monitor energy flows and adjust to changes in energy supply and demand in real-time with the aid of digital connectivity and battery energy storage systems. In good times, smart grids can be power savers as they enable electricity to be aggregated and distributed more seamlessly. This is important for accommodating intermittent electrical generation from increasingly important renewable energy sources. It can also aid in “demand response” – shifting electricity demand from peak to off-peak hours. In the case of a systemic failure, smart grids would make Taiwan’s grid more robust by allowing regional grids to function in the event of central failure.
However, Taiwan still has a long way to go before achieving such a system, according to Yeh Tsung-kuang, a professor at National Tsing Hua University’s Department of Engineering and System Science. “The persistent reliance of northern Taiwan on electricity imports from the south is both the biggest source of fragility in the grid and something that cannot be solved through grid improvements alone,” he notes.
Before finalizing any plans for better grid distribution, the authorities will also need to ensure that power plants are distributed in clusters in the island’s north. “We have an enormous amount of power going from south to north – around three gigawatts in the summer,” says Yeh. “That amount is only going to increase.”
On the day of the 303 blackout (named for March 3, 2022, the date on which it occurred), Taiwan’s grid north of the Lunchi UHV substation could have been spared if the north generated enough electricity to meet its own needs, notes Yeh. “It’s true we have underinvested in our grid infrastructure, but while we have a grid problem, we also have a capacity problem,” he says. “Our capacity problem will make the grid worse; however, just making the grid better will not solve our power generation capacity problem.”
Human errors
One way grid and power generation capacity issues intersect is in the human element of the grid: the Taipower staff who physically operate the equipment. Due to operator error – the proximate cause of both the 303 blackout and last year’s 513 blackout – Taipower staff have come under unprecedented scrutiny. In fact, the Kaohsiung Ciaotou District Prosecutors’ Office announced it would investigate the three staff members involved in the 303 blackout for violation of Article 176 of the criminal code – intentionally or negligently causing the destruction of something by means of gunpowder, steam, electricity, gas, or another explosive substance. The charge’s seriousness reflects the damage done by the outage, but frontline Taipower employees say they are terrified and exhausted as they work overtime in their struggle to keep the lights on.
“It’s like we are walking on a high wire,” says one Taipower engineer who wishes to remain anonymous. “Because power supply is so tight, we’ve been pressured to shorten the maintenance period for our power plants.”
In engineering, there is an old saying: If you don’t schedule your maintenance, it will schedule itself. And no one is more aware of that than the engineers and technicians at Taipower. “From the point of view of system stability, the maintenance period should never be skimped, says the engineer. “The inevitable result will be more accidents. And once another accident inevitably occurs, the blame will fall on another lower-level Taipower staff. This is a gross injustice.”
A culture of high-pressure deadlines and blame, including the possibility of facing criminal charges, has crushed the morale of Taipower workers, says another frontline employee. “We’re scared. We seem to be to blamed no matter what happens. And for the sake of our jobs, we stay silent, but if things go on like this, a lot of Taipower staff will go elsewhere. We don’t feel safe.”
But help is on the way, said Deputy Minister of Economic Affairs and Taipower Interim Chairman Tseng Wen-sheng in a briefing to the legislature in March. During the briefing, Tseng said an infusion of NT$100 billion from the general budget would be allocated to improving Taiwan’s grid.
Due to the woeful state of Taipower’s finances, driven in part by Taiwan’s low electricity prices, the company, while well-aware of grid issues, has not been able to address them. In the wake of gangbuster economic growth and increased demand for power, it is essential for the Taiwan government to allocate resources to help the wounded giant.
The draft plan to improve the grid has three main goals. The first is to alleviate the pressure on the “south-to-north superhighway” with additional power transmission lines. The second is to connect power plants with industrial and technology parks directly, allowing some industrial power use to bypass the main grid completely. The third is to initiate the installation of smart grids, like those suggested by NCKU’s Chiang-Chien. But Tseng posits that the current budget allocation is still insufficient. “It will probably take more than NT$100 billion,” he says. Parts of the ambitious overhaul will also take time – as long as 10 years for some reforms. In addition, Taiwan’s power problems are more than grid-deep, notes Tseng. “As long as we are relying on using power generated in the south up in the north, the burden on the central north-south artery will continue.”
(Source: https://topics.amcham.com.tw/2022/05/fixing-taiwans-grid-issues-requires-redistribution/)