Government issued the first warning and avoided major power outage in Northeast and Tokyo area

Government issued the first warning and avoided major power outage in Northeast and Tokyo area

On 22th March when electricity demand surged in the Northeast and Tokyo area due to the temperature drop caused by bad weather, the government and general power transmission and distribution business operators were pressed to respond to requests for power saving and securing stable supply of electricity. On the night of the 21st, the government issued its first power shortage warning for the Tokyo area. In the morning of 22nd, the supply-demand condition worsened also in the Tohoku area, and coverage of power shortage warnings expanded to both areas. In the Tokyo area, there was growing concern about power outages later in the evening, another round of power saving was requested. As the result, the power demand had decreased by 8:00 PM and avoided the power outage.

After the power shortage warning was announced on the night of the 21st, the Organization for Cross-regional Coordination of Transmission Operators (OCCTO) requested business operators for cooperation to increase in-house power generation by their facilities and the demand response (DR), and instructed flexible power receiving in the Tokyo Electric Power Company’s Power Grid (TEPCO`PG) area from 7:00 AM on the 22nd.

However, while electricity demand surged also in the Tohoku area in the morning on the 22nd due to bad weather, the solar power generation decreased. The electric supply to the Tokyo area was suspended due to the tight demand-and-supply, and shared supply from the Hokkaido area after 10:30 AM.
The ANRE added the Tohoku area to the target area of the power shortage warning before noon.

At the press conference which was held by the ANRE, TEPCO PG and the Tohoku Electric Power Network Company shortly after noon, it was revealed that although the power saving target is set in Tokyo area as 10% of the demand which was indicated as a guideline on the evening of the 21st, actually only 3% was achieved. The press asked a number of questions about the possibilities of planned power outages. However, the ANRE repeated that its basic policy is not to implement the planned outages as much as possible.

At the press conference around 3:00 PM, TEPCO PG announced the forecast that if demand remains at current levels, pumped water storage would run out at 8:00 PM. In this case, it pointed out that the activation of Under Frequency Relay (UFR) would cause a power outage of approximately 5 million kW in the Tohoku and Tokyo area. In order to avoid this, the ANRE and others requested further power savings of 2 million kW in capacity (10 million kWh of electricity), equivalent to 5% of demand, from 3:00 PM to 8:00 PM.