Typhoon Faxai, which caused extensive and continued power outages in Chiba Prefecture, has also focused a spotlight on problems involving safety standards and infrastructure renewal.
A focus is on whether lessons learned from the typhoon can be used in the future at a time when the severity of natural disasters has intensified amid global climate change.
As many as 930,000 households were hit by blackouts due to Faxai, the 15th named storm of the year. As of 10 p.m. Sunday, some 110,000 households were still without power.
Tokyo Electric Power Company Holdings Inc. expected power supply to return to the city of Chiba mostly by Monday, but said Sunday that about 10 more days are needed in some parts of the city, as well as the city of Futtsu and the town of Kujukuri in the east of the prefecture and the cities of Tateyama and Minamiboso, located in the south of the Boso Peninsula.
Since a heavy thunderstorm was forecast to hit the region from Sunday night to Monday morning, the firm said the recovery work could be suspended, causing further delays.
One of the reasons why the blackouts spread is the collapse of two steel towers in Kimitsu, which is estimated to have cut electricity to 100,000 households.
As it will take a long time to fix the towers, Tepco has restored electricity supply to households through unconventional transmission routes.
The industry ministry requires that the steel towers be able to withstand 144 kph winds. The collapsed towers met the requirement.
But the typhoon had a maximum instantaneous wind speed of 207 kph in Chiba’s Chuo Ward.
Industry minister Isshu Sugawara has expressed readiness to work on reinforcing power facilities.
“Due to climate change, various changes, including wind speeds and rainfall that go beyond common expectations, are occurring,” he said.
Capital investment by Tepco in its electricity supply network dropped to ¥210 billion in 2015 from some ¥900 billion in 1991.
Many people see the aging of the facilities resulting from the reduction in spending as a possible cause of the massive power outage.
Kazuyuki Shiokawa, a senior engineer at Tepco Power Grid Inc., a Tepco unit, told a news conference on Friday that maintenance and repair costs have fallen by only several percent from the 1990s, although the number of new investment projects has been decreasing.
“Reducing investment and leaving deteriorated facilities unattended is not something this company would do,” Shiokawa said.
Tepco is faced with the challenge of maintaining a strong electricity supply network at a time when it is in a severe financial situation due to the nuclear disaster at its Fukushima No. 1 plant, which was heavily damaged by the powerful March 2011 earthquake and tsunami.