*Closely watched FEPC power data for August due on Sept. 10
(Adds details)

TOKYO, Sept 2 (Reuters) - Japan's power utilities generated
13.8 percent more electricity in August than a year earlier as
the hottest summer on record spurred consumers to crank up their
air conditioners, industry data showed on Thursday.

Preliminary data released by the Electric Power System
Council of Japan (EPSCJ) showed the utilities' power generation
totalled 96.82 billion kilowatt hours in August, when some power
companies set new records for peak power generation.

The Japan Meteorological Agency said this week that Japan's
average temperature over the June-August period was the highest
since it started collecting data in 1898, exceeding the previous
record in 1994.

In July, the 10 power utilities generated 90.72 billion
kilowatt-hours of electricity, up 7.9 percent from a year earlier
as the heat wave boosted use of air conditioners, in line with
expectations of an 8.3 percent rise based on Reuters calculations
from council data.

The council, established in 2004, is a private organisation
for users of the country's power grid.

Japan's 10 main power utilities, including Asia's No.1 power
producer Tokyo Electric Power Co Inc, are the country's sole grid
operators. Other grid users include independent power producers,
such as Diamond Power Co, a Mitsubishi Corp subsidiary.

The Federation of Electric Power Companies of Japan is due to
release its more closely watched preliminary data on Sept. 10 for
the 10 power utilities' August power generation and fuel usage.
(Reporting by Osamu Tsukimori and Risa Maeda; Editing by Edmund
Klamann)