1. What is a Watts vs Lumens Calculator?

Definition: This calculator converts between light output (lumens) and power consumption (watts) based on the efficacy of the light source.

Purpose: It helps compare lighting efficiency and estimate power requirements for different lighting technologies.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( W \) — Power in watts
• \( L \) — Light output in lumens
• \( E \) — Efficacy in lumens per watt (lm/W)

Explanation: The lumens value is divided by the efficacy to determine the power consumption in watts.

3. Importance of Light Efficiency Calculation

Details: Understanding the relationship between watts and lumens helps in selecting energy-efficient lighting and comparing different light sources.

4. Using the Calculator

Tips: Enter the light output in lumens and the efficacy (default 16 lm/W for incandescent). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is efficacy in lighting?
A: Efficacy measures how efficiently a light source produces visible light (lumens per watt of power consumed).

Q2: What are typical efficacy values?
A: Incandescent: 10-17 lm/W, CFL: 35-60 lm/W, LED: 80-120+ lm/W.

Q3: Why compare watts and lumens?
A: Watts measure energy use, lumens measure light output. This helps compare different bulb types.

Q4: How do I find lumens for a bulb?
A: Check the packaging or manufacturer specifications (replaces old wattage ratings).

Q5: Does higher efficacy always mean better?
A: Generally yes for efficiency, but also consider color quality and application needs.