what is Luminous efficacy and illuminance

Luminous efficacy refers to the efficiency with which a light source converts electrical energy into visible light. In simpler terms, luminous efficacy refers to how well a lamp converts electrical energy into light. The unit of luminous efficacy is lumens per watt (lm/W).

A high luminous efficacy indicates that a light source is more energy-efficient, producing more visible light for each watt of power it uses. For example, LED lights typically have a higher luminous efficacy compared to incandescent bulbs, making them a preferred choice for energy-conscious applications.

The luminous efficacy of mainstream LED lights currently available in the market typically ranges from 80 to 180 lumens per watt (lm/W).

Specifically, high-power LEDs generally have a luminous efficacy of around 120-180 lm/W,

mid-power LEDs around 80-120 lm/W,

and low-power LEDs around 40-80 lm/W.

These figures can vary depending on the type of LED and its intended application.

Luminous efficacy is a physical concept used to describe the performance of a light source, but in practical lighting application design, the concept that has a real and intuitive physical significance is effective visual luminous efficacy. In simple terms, lighting is meant to serve the eyes, and the light energy perceived by the eyes is what is truly useful. Here, the concept of illuminance comes into play.

Illuminance, measures the amount of light that falls on a surface. It is quantified in lux (lx). One lux is equal to one lumen per square meter. High illuminance values mean that a surface is well-lit, which is essential for tasks that require good visibility. For instance, a reading area might need a higher illuminance level compared to a hallway to ensure comfort and reduce eye strain.

General industrial areas: approximately 200-300 lux
Fine work areas (such as assembly lines, precision machining): approximately 500-1000 lux
High-precision work areas (such as laboratories, quality control): approximately 1000-2000 lux or higher

Under the same area, the higher the luminous flux of the light source, that is, the higher the lumen value, the higher the illuminance will be.

In practical applications, both luminous efficacy and illuminance are critical considerations. For instance, in designing a mobile solar light tower, one would aim for a light source with high luminous efficacy to ensure that the LED lights provide sufficient illuminance to light up a large area while being energy-efficient. This is particularly important in off-grid applications where energy conservation is vital. At the same time, we must also consider the illuminance requirements of the project, which are related to both luminous efficacy and the height of the light tower.

Our current mainstream solution is a 6.5-meter telescopic pole height with four 150W solar lights (160lm/W), which achieves a balance between luminous efficacy, illuminance, and energy saving. Additionally, our light towers feature some humanized functional designs, such as dimming, timing, electric rotation, and tilt. We have completed many large-scale bidding projects and also supply global wholesalers or rental companies.

If you have a need for mobile outdoor lighting, please feel free to leave a message on the right side of this page, and we will contact you within 24 hours.