The 24-hour average for spot power prices for May 4-8 delivery in both East Japan (50Hz) and West Japan (60Hz) extended losses from the previous week. Subdued buying interest due to slack supply/demand fundamentals, as the Golden Week holidays began, sent prices further down. For May 7-8 delivery, prices also firmed up as many companies resumed operations. However, a supply/demand manager at a power producer and supplier commented "Since some factories remained closed on May 7-8, a full recovery in demand would likely occur next week, starting from May 11."

Kansai Electric Power Co (KEPCO)'s Mihama nuclear power station unit No. 3 (with a capacity of 826MW, PWR (Pressurized Water Reactor) type, in Mihama-cho, Fukui Prefecture) was shut down on the morning of May 8 due to an unplanned suspension. At around 04:08 JST on May 8, an alarm was reportedly issued by a device measuring temperature differences in the upper and lower sections of the high-pressure turbine casing. Steam leakage was confirmed around the high-pressure turbine in the central control room, and subsequently, the reactor was manually shut down at around 04:24 JST on the same day. KEPCO stated that it would investigate the cause of the steam leakage.

Looking at the East-West spread of the 24-hour average for spot power in the key areas of Tokyo and Kansai, the spread was in favor of the East at Yen 6.63 on May 4, Yen 1.54 on May 5, Yen 6.16 on May 6, Yen 3.25 on May 7, and Yen 5.59 on May 8.

The fuel market from the second week of May was as follows.

The DES Northeast Asia LNG spot prices for June 2026 delivery stood at the high $16 level per mmBtu　as of May 7, decreasing by nearly $1 from the previous weekend (May 1). Following expectations that peace talks between the US and Iran would progress, crude oil prices plummeted, dragging down LNG prices as well.

FOB Newcastle Australia thermal coal prices for May 2026 loading stood at the low $132 level per ton as of May 7, decreasing by nearly $3 from the previous weekend (May 1). This reflected declines in crude oil and natural gas prices.

Crude oil prices as of 10:00 JST on May 8 saw the NYMEX WTI contract for June 2026 delivery hovering at the low $96 level per barrel, while the ICE Brent contract for July 2026 delivery was trading at the mid-$101 level. This marked a decline of approximately $6 for WTI and $6.5 for Brent from the previous weekend (May 1). As mentioned regarding LNG, with expectations for progress in peace talks between the US and Iran and for the reopening of the Strait of Hormuz, prices came under downward pressure.

The highest actual traded price throughout the week was Yen 35.83, recorded in Tokyo on May 7. Conversely, the lowest actual traded price was Yen 0.01, recorded in West Japan on May 4, across all nine areas and for the System Price (SP) on May 5, in seven areas excluding Chubu and Hokuriku, and for the SP on May 6, and in Chugoku, Shikoku, and Kyushu on May 7-8, respectively.

The weekly average of the 24-hour spot prices by area and the weekly average volume of offers, bids, and trades are shown in the table below. The holiday season receded buying interests, reducing transactions.

Power demand in nine areas of Japan during May 4-8 was 8,888.13 mil kWh, down 7.1% from 9,564.16 mil kWh during Apr 27-May 1. The figure was down 4.8% from the corresponding period a year earlier, which was 9,333.17 mil kWh during May 5-9, 2025, after day-of-week adjustment.

Deals reported on TOCOM (Tokyo Commodity Exchange) during May 4-8 were as below.

Deals reported on EEX (European Energy Exchange) during May 4-8 were as below.

Spot power prices for the third week of May are likely to test upside resistance. With the Golden Week holidays over and industrial demand returning to normal levels, temperatures for the coming week from Southern Tohoku to Kyushu are forecast to reach 25 degrees Celsius or higher for consecutive days, making it increasingly likely that cooling demand would gradually become a factor. While many sunny days are expected, with a likelihood of cloudy conditions as well, it is unlikely that prices of Yen 0.01 would persist across multiple windows even during daytime hours. Regarding next week's price trends, a market trading manager at a power producer and supplier commented that: "We anticipate Tokyo's base price would continue to hover around Yen 20, though depending on temperatures, highs of Yen 50, seen before the holidays, could potentially be reached again during evening hours. Kansai's price is expected to be around Yen 15, but due to the unplanned suspension of Mihama nuclear power station unit No. 3, prices could potentially rise further depending on its status."