Much heat waves and tropical nights boosted electricity consumption in Japan during August. Electric power supply in the Tokyo Metropolitan area rose 6.5% from a year ago to 27.5 billion kilowatthour.
However, the demand was lower by 12.5% compared to August 2010, when temperature was higher than this year, economy was recovering from the Lehman shock slump and no one was required power saving.
Electricity demand in western Japan's Kansai area around Osaka and Kyoto was also recorded highest in this year in August at 14.6 billion kWh. But a lack of nuclear power supply forced regional users to reduce electricity consumption. The August power demand was 2.5% lower from a year ago and decreased by 11.3% from the same month in 2010.
Therefore, daily maximum electricity demand in the area has remained at enough lower than the supply capacity. The average usage rate of the daily maximum power demand during July and August was 85% of the total supply capacity, according to the Kansai Electric Power Company.
KEPCO restarted two of its nuclear power units in July due to the forecast of power supply shortage. But actual demand exceeded the red line (power supply capacity without nuclear) of the above chart only once during the past two months. The excess amount was 130,000 kilowatt which could be covered by a single gas turbine.
Spare supply capacity is always required for the stable electricity supply, also another round of heat wave may lift Japan's electricity demand even in September. However, so far the necessity for restarting the nuclear units was not so high definitly.
This could be a favourable result for anti-nuclear groups. But was the absence of serious power supply shortage without nuclear only led by the simple power saving?
Although domestic shipments of low sulfur fuel oil for power generation hit the record 430,000 barrels per day in early August, total crude oil throughput in Japan has kept year-on-year decrease in the past 11 consecutive weeks since mid-June, according to the Petroleum Association of Japan.
Japan's exports to China in the first seven months in this year fell 9.1% on year, this shows demand of materials and parts from the "world's factory" is shrinking.
Therefore, we can recognize that international economic slowdown makes Japanese manufacturers to reduce power consumption easily. It might be wrong to think that the forced power saving supresses industrial activities in Japan.
Someday when the global economy resumes strong recovery, does Japan face significant power supply shortage?
Accelerated overseas transfer of factories is likely to cap growth of domestic energy demand.