An accidental power cut at Taiwan’s largest gas-fired power plant triggered a full scale blackout on Tuesday, leading to growing scrutiny of the government’s energy policy.

The Taiwanese grid is under severe pressure thanks in part to President Tsai Ing-wen’s efforts to reshape the island’s power mix. The latest incident has led to the country’s economy minister, Lee Chih-kung, submitting his resignation.
Power outage in city 

A combination of unusually hot weather, infrastructure damage from typhoons and Tsai’s drive to abandon nuclear power left Taiwan barely able to supply sufficient electricity to residential and business users in the past week.

Matters came to ahead at 5pm Tuesday when the Tatan power plant, which accounts for almost 9 per cent of the island’s generation capacity, stopped after workers accidentally shut off its natural gas supply. The prime minister was forced to apologize after 6 million households were subsequently hit. Some of the country’s vital semiconductor production was also disrupted before power was restored at 10pm.

Six generators in the plant failed shortly before 5pm, affecting the supply of 4 million kilowatts of electricity. The blackout came amid a heatwave that saw maximum temperatures in Taipei hit 36 degrees Celsius for at least ten days running, leading to peaks in power consumption.

The government’s pledge to phase out nuclear and cut coal is now under the microscope.

The island, which plays a critical role in the world’s electronics supply chain, will rely instead under her plan on natural gas, renewables and distributed generation, which entails multiple, smaller power sources that decrease reliance on single plants and can offer greater grid stability.

The disruption Tuesday occurred when engineers replacing power supply equipment for a control system at Tatan’s metering station didn’t switch the system from automated to manual before starting the work, according to CPC Corp., which provides the plant natural gas. That resulted in two valves being automatically closed, one for about six minutes, shutting off gas supplies.

Both the operator and supplier of the plant, Taiwan Power Co. and CPC Corp., are state-run and the country’s recent difficulties have led to fears that the business sector has lost faith in Taiwan’s energy reliability.

Last week, state-run utility Taiwan Power Co. warned that the operating reserve margin, the amount of maximum capacity available above peak demand on a particular day, fell to the second-lowest on record.

“The government is promoting distributed green energy to avoid the situation where an incident at a single power station can affect the power supply for the whole country,” Tsai wrote. “We will not change course. Today’s incident only makes us more determined.”

Taiwan’s problems have been compounded by severe delays in getting new gas-fired power on to the grid, leading to calls by the Chinese National Federation of Industries to slow the pace of nuclear power plant closure.

Taiwan has mothballed one of its four nuclear power stations, and three of the remaining six remaining reactors are shut down. Calls for two of these plants to be re-opened have gone unheeded by the government. Nuclear made up 12 per cent of Taiwan’s power mix last year, down from 17 per cent in 2013, according to its Bureau of Energy.

Legislation passed in January set a goal of getting rid of nuclear power by 2025, as well as lowering the share of coal to 30 per cent and raising natural gas to 50 per cent, with the remainder coming from renewables, according to Bloomberg New Energy Finance.

Taiwan’s three shut reactors — both units at Jinshan and the No. 2 unit at Kuosheng — have combined capacity of almost 2.26 gigawatts, according to the Atomic Energy Council. The Tatan plant accidentally shut on Tuesday can produce 4.38 gigawatts, according to Taiwan Power Co., known as Taipower. The country’s total generation capacity is 49.9 gigawatts, according to Bureau of Energy, Ministry of Economic Affairs.