Japanese conversion to LED lights would slash energy usage

June 28, 2011
Converting the 1.6-billion lights in Japan to LEDs would be unfeasibly expensive, but would save a massive amount of energy, says a report.
A study in Japan has concluded that the country’s annual energy consumption could be slashed by 9 percent if it were possible to replace all the fluorescent and incandescent lights used in Japan with LED lights. The results were reported in an article in the Mainichi Daily News.

The study, by the Institute of Energy Economics (IEE), a foundation supervised by the Ministry of Economy, Trade and Industry (METI), estimated that 92.2 billion kWh of electricity – worth the output of 13 nuclear reactors – would be saved annually if the switch was made.

"Promoting the introduction of LED lights will serve as energy-saving measures that have immediate effects and sustainability," said a representative of the IEE, which conducted the calculation in response to the accident at the Fukushima nuclear power plant and the ensuing public attention to the nation's energy policy.

There are an estimated 1.6 billion lights in use in Japan, of which 870 million are in households, 580 million in offices and commercial buildings, and 160 million in the manufacturing sector. As the Table shows, the amount of energy saved would be greatest in the offices/commercial sector.

Number of lights Annual energy consumption
(billion kWh)
Incandescent & fluorescent
Annual energy consumption
(billion kWh)
LEDs only
Savings (billion kWh)
Households 870 million38.214.124.1
Offices & commercial buildings580 million89.134.654.5
Manufacturing sector160 million23.39.713.6
Total1.6 billion150.658.492.2

However, the initial cost of installing LED lamps is very high, says the study, estimating that LED lamps cost 20 times the price of incandescent bulbs and more than twice that of a fluorescent bulb. If all the incandescent and fluorescent lights were replaced with LED counterparts, the initial cost would be 15.7 trillion yen ($194 billion).

Replacing all the incandescent lights with LED lamps is more feasible, since this would have an initial cost of 850 billion yen ($10.5 billion), but would save 27.3 billion kWh annually, worth the output of four nuclear reactors, according to the institute.

"Replacing incandescent lights with LED lights at offices and households, which can be easily done, will help save energy. In that way, we'll be able to introduce LED lights in phases," said an IEE official.