Light emitting diodes (LEDs) are semiconductor diodes that generate light by collecting charges present in a semiconductor at a relevant energy band gap. In the beginning, LED applications were mainly focused on colored LEDs that generate colored light without using dichroic or subtractive filters unlike other conventional light sources.
LEDs are classified into chip on board (COB) LEDs, surface mounted device LEDs and T-type LEDs based on their shapes. LEDs are widely used in the TV industry. According to an analysis conducted by BBC, LEDs used in TV studios can save energy costs up to 30-50% and considerably reduce carbon dioxide emissions when compared to other lightings. As LEDs complement the use of high-definition programs and 3D in TV, they are best suited for filming applications. Owing to their low maintenance and energy costs, LED lightings also find applications in healthcare, educational institutions, and airports.
In the TV industry, the energy costs due to lighting products alone would account for 80% of the total cost. This is due to the fact that more amount of energy is required to power the lights and other gadgets. Hence, it is necessary to use a cost-effective, low-energy lighting system that meets the following criteria:
- Better energy management
- Efficient design
- Efficient equipment performance
In addition, implementation of lighting controls like time control and absence detections system in dimming rooms, storage rooms and other technical areas would further reduce energy consumption. Currently used LED lightings and fluorescent soft lights guarantee high performance with compact structure. These lights can save up to 75% of energy utilized by tungsten soft lights. A study conducted by the Northeast Group reported that LED-based streetlights implemented in the US were found to be more efficient in saving energy costs and maintenance by about 60%.
Although incandescent lights are inexpensive to use, they have been proved to be hazardous to the environment and humans. These lights tend to release carbon dioxide from coal that is used to power them and thus promote global warming. On the other hand, fluorescent lights consist of mercury, which can be hazardous to humans due to its high toxicity.
LEDs are free from these problems. They do not pollute the environment and are free from IR and UV radiations as they contain high blue light content.
According to a survey conducted by the Northeast Group recently, nearly 95% of the cities that use LED streetlights across US were appeased with the performance and quality of the LED lights. Law enforcement officials, in particular were happy with the implementation of these lights as they enhance public safety and visibility on roads. The key benefits of LED streetlights are:
- Convenient to turn off and on
- Better dimming function
- Less maintenance cost
- Reduced energy consumption
- High efficiency
- Remote monitoring features.
The study found out that around 400 cities in the US have already switched to LED streetlights. Northeast Group also found out that 25 vendors were involved in LED streetlight business in the US and the market will likely to grow further with a wide range of LED lighting solutions available. In addition, most of the cities are looking to invest in smart LED streetlights to reduce the overall energy consumption of the country.
LED Street Lights on Victor Street, Torrance, CA
Summary of LED Lights
LEDs need minimum maintenance as they feature high impact resistance, prolonged service life, small form factor and compact design. The energy consumed by LEDs is extremely low and as a result they tend to have high luminous efficacy.
An electronic control gear needs to be installed in LEDs for maintaining the operating current constant. LEDs start quickly without requiring warm-up time and instantly respond to dimming and other controls. Owing to the fact that the light intensity decreases when LEDs are dimmed, the colour temperature of LEDs is kept constant. However, lowering of color deviations and color consistency are some of the major challenges currently faced by the LED manufacturers. Nevertheless, LED lights definitely make the globe brighter, better and more sustainable.
Sources and Further Reading