According to the Institute of Energy Economics (IEE) of Japan, a foundation supervised by the Ministry of Economy, Trade and Industry, if LED lights replace all the fluorescent and incandescent lights used in the country, 92.2 billion kilowatts of electricity -- worth the output of 13 nuclear reactors -- would be saved, that is, the annual domestic power consumption would be slashed by 9 percent.

A group of researchers led by Yoshiaki Shibata at the institute conducted the calculation. According to their survey, among an estimated 1.6 billion lights being used in Japan, 870 million of them at households, 580 million at offices and commercial buildings and 160 million in the manufacturing sector.

Translated into annual power consumption, they equal to 38.2 billion kilowatts per hour of electricity is used at households, 89.1 billion kilowatts per hour at offices and 23.3 billion kilowatts per hour in the manufacturing industry, totaling 150.6 billion kilowatts per hour.

It will make sense when all lights replaced LED lights, as the annual power consumption is estimated to decline to 14.1 billion kilowatts per hour at households, 34.6 billion kilowatts per hour at offices and 9.7 billion kilowatts per hour in the manufacturing sector, totaling 58.4 billion kilowatts.