How long will Japan bear without nuclear power?

Although most of Japanese nuclear plants are still shut, Japan seems to succeed to get over winter without nuclear power supply as same as the previous summer demand season.

It was fortunately helped by relatively warm weather in January, therefore, Japan is still not able to decide to give up nuclear units.

Electricity supply by Japanese ten major utility firms fell 1.7% from a year ago to 8.6 billion kilowatt hour, according to the Federation of Electric Power Companies. It was the first year-on-year decrease in the past three months.
Although cold weather sustained electricity demand during December, power saving directly affected demand in January.

In the Kansai Electric Power Company's business area during December, there were five days when power supply capacity were shortage if the company didn't resume two nuclear units in mid-2012. However, KEPCO's average capacity utilization in January fell 5 points from the previous month to 79%.

Average temperature in Osaka in December was 1.5 degree Celsius lower than a year ago and 2.0 degree below the 30-year average. But January average was only 0.4 degree lower from a year ago and 0.8 degree below the 30-year average. Moreover, average temperature is over the previous year level and the historical average in the first half of February.

Meanwhile, average capacity utilization of Tokyo Electric Power Company has been about 90% in the past couple of months. It was relatively less spear availability compared to KEPCO.

TEPCO's average capacity utilization during 2012 was 85.5%. The company has gotten over heat waves and cold weather without nuclear plants, but its supply capacity was critically close to the limit during the high-demand season.
The company may not be able to accommodate the possible growth of demand in case of economic recovery.

Japanese stock market has been firmer due to the positive forecasts triggered by the government's easing policies. However, the country's industrial index have not shown actual signs of recovery.
Crude oil processing that indicates energy demand has already finished the slump but has not seemed to begin rebound.

Since stock market is said to preempt the real economy, Japanese manufacturers might increase activities in the near future. Energy demand is likely to rise at that time.

Previously, it was easy to reduce electricity usage due to the industrial slump. But are Japanese utility firms able to get over the coming summer season?
Japanese manufacturers could maintain low power usage when they move factories to overseas further, but the weaker yen may inhibit it.

Since the weaker yen will lift imported thermal power fuel prices on the other hand, requests to resume nuclear plants are likely to expand in the near future.