How to calculate the light efficiency of LED street lights?

Time of Release : 2024-01-23

Calculating the light efficiency of LED street lights requires considering two main factors: luminous efficiency and power efficiency.

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Luminous efficiency Luminous efficiency refers to the ratio between the visible light power generated by LED street lights and the input power. The luminous efficiency of LED chips is usually measured in luminous flux (lumens). Lumens (lm) is a unit used to measure luminous flux in the International System of Units, and represents the brightness perceived by the human eye.


To calculate the luminous efficiency of an LED chip, you need to know its luminous flux and power consumption. Luminous flux can be obtained from the technical parameters provided by LED manufacturers, usually expressed in lumens per watt (lm/W). The power consumption can be obtained from the power parameters of the LED street light, usually in watts (W).

The luminous efficiency of LED street lights can be calculated by the following formula:

Luminous efficiency = luminous flux / power consumption

Power efficiency Power efficiency refers to the energy conversion efficiency of the LED street light power supply system. Due to the presence of components such as power transformers and power drivers, LED street lights will have a certain amount of energy loss before the power is input to the LED chip. Therefore, the power efficiency directly affects the overall light efficiency of LED street lights.

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To calculate the power efficiency of an LED street light, you need to know the total power of the LED street light and the actual power supplied. The total power refers to the power consumed by the LED street light from the power grid, and the actual power supply refers to the effective power supplied to the LED chip.

The power efficiency of LED street lights can be calculated by the following formula:

Power efficiency = actual power supply / total power

Light efficiency Light efficiency is the result of the comprehensive luminous efficiency and power efficiency of LED street lights. It represents the overall efficiency of LED street lights in converting electrical energy into visible light.


The light efficiency of LED street lights can be calculated by the following formula:

Light efficiency = luminous efficiency × power efficiency

Light efficiency is usually expressed in lumens per watt (lm/W). The higher the value, the better the lighting performance of the LED street light.

It should be noted that luminous efficiency is only an indicator for evaluating the performance of LED street lights. Other factors such as color temperature, color rendering index, etc. also need to be considered. At the same time, the performance of LED street lights from different manufacturers may vary. Therefore, when selecting LED street lights, factors such as light efficiency, quality, reliability, and price should be comprehensively considered.

To sum up, calculating the luminous efficiency of LED street lights requires considering luminous efficiency and power efficiency. By dividing the luminous flux of the LED chip by the power consumption, the luminous efficiency can be obtained; by dividing the actual power supply by the total power, the power efficiency can be obtained. Finally, by multiplying the luminous efficiency and the power efficiency, the light efficiency of the LED street light can be obtained. The higher the light efficiency, the better the lighting performance of LED street lights. When selecting and evaluating LED street lights, factors such as light efficiency, quality, reliability and price should be comprehensively considered.