Light

Guide

LED ROI Calculator

LED ROI calculator: compare legacy vs. LED bulb watts, daily and annual savings, CO₂ reduction, and payback days for a single fixture—free lighting upgrade math.

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LED ROI is operating savings minus bulb cost—not lumens on the box. This guide walks through the LED ROI calculator: legacy watts, LED watts, hours per day, electricity rate, and bulb price to see payback and annual dollars saved.

Benefits

  • Daily savings = (legacy W − LED W) × hours ÷ 1,000 × $/kWh.
  • Payback days = LED bulb price ÷ daily $ savings when LED uses less power.
  • Shows monthly/annual cost, kWh saved, and CO₂ reduction alongside payback.

How it works

  1. Enter existing bulb watts and LED replacement watts (lower is required for payback).
  2. Set hours of use per day, electricity rate ($/kWh), and LED bulb price.
  3. Review payback time, annual savings, and before/after operating cost bars.

FAQ

How do I calculate LED ROI?

Daily savings ≈ (legacy W − LED W) × hours/day ÷ 1000 × $/kWh. Payback days ≈ LED price ÷ daily savings. Example: 60 W → 9 W, 5 h/day, $0.14/kWh → ~$0.036/day saved; $4 bulb → ~111 days payback. Annual savings ≈ daily × 365.

What is a good LED payback period?

Many single-bulb swaps pay back in 2–6 months for high-use fixtures (kitchen, porch, office). Low-use closets may take longer—ROI still improves over the LED’s life. Under ~90 days is common for 4–6 h/day incandescent replacements.

Does this include replacing multiple bulbs?

This tool models one fixture. For whole-home retrofits with many bulbs and replacement schedules, use the LED vs. Incandescent ROI calculator—or sum one row per fixture here.

Technical specifications

  • Daily kWh saved = (legacy_W − LED_W) × hours ÷ 1000.
  • Daily savings $ = daily_kWh_saved × $/kWh.
  • Payback_days = LED_price ÷ daily_savings (when savings > 0).
  • Related: led-vs-incandescent-roi, lighting-circuit-load, electricity-bill.

Operating cost, not sticker price

A $2 LED that saves $0.04/day beats a $1 LED that saves $0.01/day on ROI—even if both say “equivalent wattage.” Match lumens and color temperature, then let watts and run hours drive payback. The calculator ignores legacy bulb replacements; energy savings repeat every day the LED runs.

High-use fixtures first

Kitchen cans, porch lights, and desk lamps dominate hours. Swap those before guest-room closets—the same bulb price returns faster when hours per day are high. Payback days from this tool tell you which sockets to hit on weekend one of a retrofit.