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PEOPLE in Japan may have to throw out their household appliances and buy new
ones if the government agrees to proposals to raise the voltage of the
country’s electrical power grid.

Japan and North Korea are the only countries still using 100 volts as
standard. But Japanese power companies represented by the Electrical Technology
Research Association, and appliance manufacturers represented by the Japan
Electrical Manufacturers’ Association, say the 100-volt grid is outdated and
inefficient. The two organisations have issued separate reports recommending an
upgrade to around 200 volts within the next 15 years.

At the moment, electricity is transmitted along power lines at 6600 volts
before being stepped down by transformers to 100 volts for use in the home.
Factories and other plants that use higher voltages have to use step-up
transformers. The reports recommend raising the transmission voltage to 22,000
volts and then stepping it down to about 230 volts—the voltage used in
most of the world outside North America.

The power companies say an upgraded grid would be more efficient. The lower
the transmission voltage, the higher the current—and that causes greater
power loss due to heating. Raising voltages along transmission lines would lower
the current and cut energy losses. Companies say that the change would save 7
billion kilowatt-hours a year—almost 1 per cent of Japan’s total
electricity consumption—and result in a 3-million-tonne cut in carbon
dioxide emissions.

Manufacturers of electrical goods say household appliances would also be more
efficient, and the 80 billion yen (£47 million) a year that would have to
be spent on new white goods capable of running on 230 volts would boost Japan’s
flagging economy. But consumers may not be so keen to fork out that much money.