Tokyo businesses and residents were told to limit their use of electricity on Tuesday to avoid plunging the world’s biggest metropolitan sprawl into a power blackout.
The warning, which affected the capital as well as surrounding areas that are home to about 45mn people, followed a violent earthquake in north-eastern Japan last week that caused several thermal power plants to suspend operations. The quake piled pressure on a grid already strained by the 11-year closure of most of the country’s nuclear facilities.
The blackout alert, issued by the Ministry of Economy, Trade and Industry, was the first of its type since a system was installed in the aftermath of the 2011 Tohoku quake.
The area affected is covered by the Tokyo Electric Power Company (Tepco), whose reputation remains tarnished by the 2011 meltdowns at the Fukushima Daiichi nuclear power facility. Later on Tuesday, a second warning was issued to areas covered by the Tohoku Electric Power Company in the north-east of the country.
The warning urged companies and individual homes to collectively cut their consumption by about 60mn kilowatt-hours, or about 10 per cent of the estimated demand from 8am to 11pm.
In a statement after 11pm, Tepco thanked its customers and wider society for power-saving efforts that it said had allowed it to continue the stable supply of electricity on Tuesday. But the company said it would continue to request they conserve electricity where this did not cause “difficulty in daily life”.
The alarm had been sounded after power reserves in the area fell below 3 per cent of total capacity. Between 11am and noon, the ratio of demand to power supply capacity hit 103 per cent, the highest of four levels of severity, according to Tepco.
Koichi Hagiuda, the trade minister, called for co-operation to save electricity “as much as possible”, saying the supply of electricity was expected to be extremely tight.
The power crunch coincided with unusually cold weather around Tokyo, with snow forecast for Tuesday afternoon.
On the night of last week’s 7.4 magnitude earthquake, more than 2mn homes across nine prefectures, including Tokyo, suffered power cuts that in some cases lasted until the following day. The quake initially forced more than 6GW of power capacity to go offline, of which roughly half remains suspended, according to the government.
Even before last week’s quake, which caused three deaths and 225 injuries, senior policymakers within the ruling Liberal Democratic party had privately discussed the need for a “national drive” to convince people to use less electricity as the Russian invasion of Ukraine drove up global energy prices.
Yuriy Humber, founder of energy consultancy Japan NRG, said the warning was a reminder of Japan’s heavy reliance on thermal energy, mostly coal and gas.
“I’m a bit surprised as to how prolonged this is likely to be,” said Humber, who added that the prospect of asking the world’s oldest population to conserve power was something the government would be keen to avoid in an election year.
The fact that the alert had been issued, he said, suggested that the damage done by last week’s tremors could be greater than acknowledged.
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