1. What is Lumens to Watts Conversion?

The Lumens to Watts conversion helps determine the power consumption (watts) of a light source based on its brightness (lumens) and energy efficiency (efficacy in lumens per watt). This is particularly useful when comparing different lighting technologies.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( Lumens \) — Total luminous flux (brightness)
• \( Efficacy \) — Lumens per watt (energy efficiency)
• \( Watts \) — Power consumption

Explanation: The formula divides the total light output (lumens) by the efficiency (how many lumens the light source produces per watt of power consumed).

3. Importance of Efficacy in Lighting

Details: Efficacy measures how efficiently a light source converts electrical power into visible light. Higher efficacy means more light with less energy, leading to energy savings and lower electricity bills.

4. Using the Calculator

Tips: Enter the lumens value (brightness) and the efficacy value (lumens per watt) for your light source. Both values must be greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What are typical efficacy values for different bulbs?
A: Incandescent: 10-17 lm/W, Halogen: 12-22 lm/W, CFL: 40-70 lm/W, LED: 60-120+ lm/W.

Q2: Why convert lumens to watts?
A: To compare energy consumption between different light sources that produce the same brightness.

Q3: How accurate is this calculation?
A: It provides a good estimate, but actual power consumption may vary slightly due to driver/ballast losses.

Q4: Where can I find lumens and efficacy information?
A: Usually printed on bulb packaging or available in product specifications from manufacturers.

Q5: Does this work for all light types?
A: Yes, the formula applies universally, but efficacy values vary significantly between technologies.