Light-emitting diode (LED) traffic lights are more energy-efficient and have a longer lifetime than conventional incandescent traffic lights.    By using LED traffic lights in favour of conventional traffic lights, it is estimated that approximately HK$7.6 million of energy charge could be saved per annum. This will reduce CO2 emissions by 5,300 tonnes.

What is it?

All the conventional traffic signals at 1,900 junctions currently employing incandescent lamps bulbs in Hong Kong will be replaced by LED modules in three phases:

Phase 1 – about 400 junctions on Hong Kong Island
Phase 2 – about 670 junctions in Kowloon
Phase 3 – about 830 junctions in the New Territories

The three phases will commence in September 2008, August 2009 and August 2010 for completion by October 2009, January 2011 and July 2012 respectively.


The project will be funded under the Public Works Programme, Capital Works Reserve Fund.

How does it work?

Conventional traffic signals employ incandescent lamps.  They are not energy-efficient, and the on-going energy charge contributes a high proportion of the recurrent cost.  Comparing with the conventional traffic signals, LED traffic signals consume much less electricity energy (about one-third or less energy) and have longer design life (over 10 years).

LED signals will generate savings of recurrent cost within their design life, offsetting the higher capital cost as compared with the conventional traffic signals.

CO2 Emissions Reductions

Annual saving of 7.6 million kWh electrical energy will reduce CO2 emissions by 5300 tonnes.

Energy Efficiency

Savings were demonstrated in the LED traffic signals pilot scheme completed in early 2008 at 100 junctions. The total energy consumption of the whole junction including the traffic signal controller, traffic lights and electronics audible traffic signals, pushbuttons was reduced to about one-third before adopting LED.

Next steps

Adoption of LED on other applications shall be reviewed and the availability of new technology shall be closely monitored.

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