June 26, 2017: There is no doubt that LED lighting is now a dominant semiconductor light source for general lighting applications. In addition, it is a known fact that efficiency of LED lighting is greater as compared to traditional lighting systems. However, as far as LED lighting system goes, one major concern is its efficiency and how to calculate it. The efficiency of light sources is generally measured in lumens per watt (lm/W) or by radiometric power. It is important to know about the impacts of LED efficiency before switching over to LED lighting or buying LED lights. Let’s find out the major factors that determine efficiency of LED lighting.
Color temperature is one of the chief factors that determine LED efficiency. Color temperature not only influences luminous efficacy but can also be used within the structure of present lighting regulations as a lever for the competent planning of lighting solutions. LEDs with a high correlated color temperature (CCT) (5000K) generally have a higher efficiency than those with a relatively low CCT (3000K).
In order to generate white light with an LED, usually a semiconductor chip that releases blue light is used. Some of the light gets converted into light with longer wavelengths through phosphor or converter mix. Adding together such colors produces white light, and the conversion method involves losses, which amplify with the wavelength of the transformed light. This increase in loss is mostly due to the variation in energy between light at a lower energy level (red light) and light at a higher energy level (blue light). Reducing losses involves exact alignment of the release and absorption of wavelengths of the converter.
The composition of the color range on the basis of the option of an appropriate converter has an important influence on LED efficiency. The converter mix is developed specially for diverse CRIs, and the differences between CRI 70, 80, and >90 is seen in the rendering of red tones in a clear manner.
A high proportion of long-wave light is required for reproduction of such tones, which refers to the light at the red end of the color range. The liberty to select the color temperature and CRI of an LED, nevertheless, is limited by conditions, rules along specific requirements of a particular application.
The LED opto-semiconductor provides a good dimension or current density in which the efficiency can not only be adjusted but also set on an application-specific basis by the luminaire manufacturer. LEDs are typically categorized on the basis of their brightness and color for some operating current. In case of specific grouping conditions, there is a typical efficiency that is adjustable to go with the application and the required level of luminous efficacy.
There are also other parameters to determine LED efficiency. Some of the major parameters include maximum operating conditions to be met and, operating temperature. The complete luminous flux of the LED naturally changes at dual operating points.
Vital cost reductions
In today’s time, LEDs have become brighter and more efficient. However, there are few lighting applications that do not essentially require better efficiency. Nonetheless, the demand for brighter and more efficient LEDs is increasing with each passing day. And the reason behind such increasing demands is that efficient LEDs pave way for vital reductions.
Hence, the selection of color temperature along with the CRI presents an important influence on LED efficiency. Particularly, this means that the higher the color temperature, the better the LED efficiency and the higher the CRI, the lower the LED efficiency. Here, a vital contrast between LEDs and traditional lighting systems is that the LED efficiency is adjustable through the operating current. This alternative needs to be taken into consideration with reference to LED systems since noteworthy savings in LED costs might be incurred.