LEDs are fast replacing regular filament bulbs in many spaces. This is largely due to the ability of LEDs to save energy and provide a better quality of light. LEDs can be controlled to vary their intensity depending on traffic density and other factors. A typical HPS lamp uses 75% more electricity than an LED lamp. The quality of the LED light is higher, despite the lower power consumption.
There has been an argument that LED lights are 5 times more expensive to buy and install but a study showed that the street lights can pay for themselves within 6 years through the reduced electricity and recurrent maintenance costs.
Where LED street lighting has been tested, the problem that kept coming up was glare. The good news is that there are researchers in Germany who have made low-glare LEDs to be used for streetlighting. Here is our argument for the adoption of low-glare LEDs for street lights.
One of the biggest drawbacks associated with the HPS lamps that are used for streetlights in many areas, is that they contribute to the mercury dumped on land. HPS lights carry an estimated 6mg/100W of mercury while LEDs carry zero. The use of LEDs is also likely to reduce the emission of CO2 gases by 125 tons per year.
It is possible to dim an HPS lamp. However, it is not easy to do so. The reason for that is special ballast is required to dim HPS lamps and the dimming limit is 50%. LEDs on the other hand can be dimmed easily. All that is needed is a small program to run the dimming. LEDs and the Internet of Things are easily compatible, making it possible to control LED lights remotely. A LED streetlight has a low dimming limit of 10%, which means it can be dimmed by more than 90%.
The HPS lamp is likely to last between 10,000 and 24,000 hours before it burns up and needs replacing. While that is a decent mileage, LED lights can last well over 50,000 hours. The financial implication is that money spent on acquiring 2 HPS lamps can go towards the acquisition of an LED lamp.
The most exciting development in LEDs for streetlighting is the discovery of a way through which to reduce glare. This has been a problem because it increases the risk of accidents happening. With this new development, there simply is no logical reason why streetlights should not be LED-lit.
EDITORS NOTE: The featured image is by by Sergey Zolkin.