1. What is a Lumens per Watt LED Calculator?

Definition: This calculator determines the luminous efficacy of an LED light source by measuring how efficiently it produces visible light (lumens per watt).

Purpose: It helps compare energy efficiency of different lighting solutions and evaluate LED performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• Efficacy — Light output per unit of power (lumens per watt)
• Lumens — Total visible light emitted (lm)
• Watts — Power consumed (W)

Explanation: Higher efficacy values indicate more energy-efficient lighting, producing more light with less power.

3. Importance of Efficacy Calculation

Details: Understanding lumens per watt helps in selecting energy-efficient lighting, reducing electricity costs, and meeting sustainability goals.

4. Using the Calculator

Tips: Enter the total lumens (light output) and watts (power consumption) from the LED specifications. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a good lumens per watt ratio?
A: Modern LEDs typically range from 80-150 lm/W. Values above 100 lm/W are considered excellent.

Q2: How does this compare to traditional lighting?
A: Incandescent bulbs are about 10-17 lm/W, CFLs 40-70 lm/W, making LEDs significantly more efficient.

Q3: Where can I find lumens and watts information?
A: These specifications are listed on LED packaging or manufacturer datasheets.

Q4: Does higher efficacy mean better light quality?
A: Not necessarily. Efficacy measures efficiency, while CRI (Color Rendering Index) measures light quality.

Q5: Why does efficacy matter for energy savings?
A: Higher efficacy means more light for the same electricity, reducing energy costs over time.