Why is Japan, the world’s third-largest economy, under threat from a megapower cut?

For the first time in modern history, the Government of Japan issued a warning to the public on Tuesday morning against the risk of a major power outage in the Tokyo area. Authorities want businesses and individuals to reduce power consumption as much as possible, as a new wave of cold hits the center of the archipelago and large electricians deprived of several power plants can no longer meet demand. I am asking for.

Already victims of these shortages, more than 2,000 households went out of power in the prefectures adjacent to the Japanese capital at the beginning of the afternoon, even before authorities peaked in consumption.

Risk of serious incidents

To avoid major accidents, the Ministry of Economy, Trade and Industry (METI) and TEPCO, the leading electrician supplying the capital, are urging the population to reduce normal electricity consumption by at least 10%. increase. Winter level. Therefore, the ministry urged families to turn off unnecessary lights and not increase heating above 20 ° C.

As the snow returns to parts of the country, electricians are particularly worried about the surge in consumption at the end of the day. “Demand already temporarily exceeded TEPCO’s production this Tuesday morning, and electricians in other regions probably had to supply it to the region,” said EnergyPool Japan Group CEO and COO. One Arandadi explains.


This power supply, which has traditionally been tense in Japan, has been complicated by the sudden closure of several thermal power plants in northern Tokyo since last week after a major earthquake. Six power plants connected to the TEPCO and Tohoku Electric Power networks are still shut down for security checks after the earthquake on Wednesday night. The epicenter was off the coast of Fukushima. Northeast coast of Japan.

If they are unaffected, solar farms will be punished by bad weather in most areas. And since the disaster at the Fukushima Daiichi Nuclear Power Station in March 2011, most of the nuclear power plants have been shut down. But this is no longer the case, “recalls Alan Daddy, who still points out the peculiarities of the Japanese system.

Unlike European countries, which can call their neighbors in the event of a problem with their network, Japan needs to meet their needs. For geopolitical or geographical reasons, there are no power exchange contracts with South Korea, Russia, or China.

Two different frequencies

In addition, its internal organization complicates the flow between electricians who control production and supply in different regions. Japan’s power grid is still divided into two regions with different AC frequencies. The southwestern part of the country operates at a current of 60 Hz, the northeastern part is supplied with a current of 50 hertz, and all flow exchanges must go through a large frequency converter.

These tensions will reinstate the debate over the robustness of the Japanese network if authorities hope that temperatures will rise and return to normal in the coming days. “Since the power outage in Hokkaido three years ago, the country has already talked a lot about it. Russia’s gas crisis has also recently questioned it,” he said. Energy pool experts expect Russia to look to a number of solutions (production sources, storage, etc.) in the coming years in an attempt to regain flexibility. That network.