​The link you've provided leads to a "Lumens to Watts" calculator, which is a tool used to convert the brightness of a light source (measured in lumens) to its power consumption (measured in watts). This conversion is particularly useful when comparing the energy efficiency of different lighting technologies, such as incandescent bulbs, compact fluorescent lamps (CFLs), and light-emitting diodes (LEDs).

Understanding Lumens and Watts:

• Lumens (lm): A measure of the total amount of visible light emitted by a source. Higher lumens indicate a brighter light.
  
  

• Watts (W): A measure of electrical power consumption. In lighting, it indicates the amount of energy a bulb uses.
  
  

Traditionally, consumers selected light bulbs based on wattage, associating higher wattage with brighter light. However, with advancements in lighting technology, especially with the introduction of LEDs, bulbs now produce more light (lumens) while consuming less power (watts). Therefore, it's more accurate to consider lumens when selecting bulbs for desired brightness and watts for energy consumption.

Using the Lumens to Watts Calculator:

1. Enter Luminous Flux in Lumens: Input the brightness level you desire. For example, a standard 60W incandescent bulb produces about 800 lumens.
   
   

2. Select Light Source or Enter Luminous Efficacy: Choose the type of light source (e.g., LED, incandescent) or manually enter its luminous efficacy (measured in lumens per watt, lm/W). Luminous efficacy indicates how efficiently a light source converts electrical power into visible light.
   
   

3. Calculate Power Consumption: The calculator will compute the power consumption in watts based on the provided luminous flux and efficacy.
   
   

Example Calculation:

If you want to know the power consumption of an LED bulb that emits 800 lumens:

• Luminous Efficacy of LED: Typically between 80-100 lm/W.
  
  

• Calculation: Power (W) = Luminous Flux (lm) / Luminous Efficacy (lm/W)
  
  For an efficacy of 100 lm/W:
  
  Power (W) = 800 lm / 100 lm/W = 8W
  
  

This means an LED bulb producing 800 lumens would consume approximately 8 watts of power.

Luminous Efficacy Reference Table:

Light Source Type

Luminous Efficacy (lm/W)

Incandescent Bulb

12-18

Halogen Lamp

16-29

Compact Fluorescent Lamp (CFL)

40-60

LED Lamp

80-100

Note: These values are typical averages; actual efficacy can vary based on specific products and manufacturers.

By using the lumens to watts calculator, you can make informed decisions about lighting options that provide the desired brightness while optimizing energy consumption.