Report estimates energy-saving potential of LED lamps in Japan (MAGAZINE)

July 19, 2011
A recent report issued by Japan’s Institute of Energy Economics (IEEJ) highlighted the opportunities afforded by LED lighting.

This article was published in the July/August 2011 issue of LEDs Magazine.

View the Table of Contents and download the PDF file of the complete July/August 2011 issue.


The Institute of Energy Economics, Japan ( recently published a report on the electricity-saving potential of LED lighting and concluded that if all lighting in Japan was switched to LEDs, the total potential savings would amount to 92.2 TWh/year. This figure is equivalent to 9% of Japan’s current total energy consumption. Fig. 1 (previous page) breaks down the savings by sector, and shows that the greatest potential exists in offices and commercial buildings.

Total lamps (million) Price per replacement LED lamp (¥)Total initial cost (trillion ¥)Payback periodElectricity savings (TWh/yr)
Incandescent lamps3402000-30000.81 yr 5 mo27.3
Fluorescent lamps (straight tube)69010,000-25,000*9.69 yr 11 mo49.7
Fluorescent lamps (circular lamps)3507000-15,0003.518 yr 6 mo6.8
HID lamps20100,000*1.810 yr 11 mo8.4

Table 1. Cost and payback periods for replacing different lamp types with LED lamps. (*Includes possible infrastructure and labor costs required to make the changes.)

The report says that the switch would cost ¥15.7 trillion (around $197 billion), due to the current high cost of LED lamps compared with ¥100 for incandescent bulbs and ¥1000-1500 for CFLs. However the cost of replacing all the 340 million incandescent lamps would be ¥800 billion (around $9.9 billion). Such a move would lead to very significant savings of 27.3 TWh/year, as well as by far the shortest payback period.

The report also says that the cost of achieving the electricity savings (see Japan’s Eco-point Program transforms market for LED lamps) would be ¥1.3/kWh for incandescent lamps, based on a 40,000-hour lifetime. The figure is ¥14-17/kWh for replacing other technologies, and ¥9.2/kWh on average. In comparison, the cost of photovoltaic power generation is ¥40-50/kWh.

The report notes that households are highly sensitive to initial cost, so eco-point and other discounting measures are likely to be effective in promoting the spread of LED lamps. Meanwhile, businesses may require energy-conversation tax incentives and other subsidies to reduce the burden of up-front investment.