Advantages of the use of solar cells and light emitting diodes (LED) for traffic signal lights for the current power crises in Sri Lanka

Abstract

During power failures and power cuts road users suffer immense difficulties due to non-availability of traffic signal lights. Use of solar cells with lead acid accumulators to provide required power and the use of light emitting diode (LED) displays to function as signal lamps to reduce the stored power consumption will be a feasible solution for the same. In addition to the low power consumption of LED displays, it is possible to use the same display to indicate different directions by having different switching circuits. Since the LED display consists of a number of LEDs, visibility from side ways is better than the conventional signal lamp having a single light source. Failure of the lamp in the conventional signals halts the entire operation of the signal lamp but in the case of failures of few LEOs in a matrix will not cease the entire operation. The other major advantage is during the installation of new signal posts; it is possible to erect the same as a wireless installation. Solar panel with an accumulator (lead acid battery) can provide power while infrared sensors and diodes could be used to transfer signals between each signal post; hence it is not necessary to dig across the road for control and power cables.Considering the signal light requirement for the whole country, the above solution will have a considerable impact on the national power grid.