A project for introducing power cables of a thicker diameter has been undertaken since 2007, commissioned by Japan’s Ministry of Economy, Trade and Industry. The project was established based on the results of a study by the Japanese Electric Wire & Cable Maker’s Association showing that power distribution losses can be reduced by about a half by using wires and cables of a larger diameter.

Through the efforts of utility companies, power transmission and distribution losses in Japan are already at 7 percent between the power plants and the receiving ends of utility customers, and at 4 percent between the receiving ends to each load end, which is low compared with other countries. However, electricity users are still paying the cost of the losses, and further reduction has been a challenge.

It is estimated that about nine million tons of carbon dioxide emissions can be reduced annually by replacing all wires in factories and buildings in Japan with proper-size ones. A verification test of actually replacing cables in a factory proved the effects of cutting the transmission cost were as estimated.

The project team is now working to establish an “environmentally friendly power current list (tentative),” a list of standardized criteria for selecting the proper wire size. It hopes the list will be made the national standard in 2011 and adopted by the International Electrotechnical Commission (IEC) in 2012.