LED vs Incandescent Bulbs — How Much Money Can You Actually Save?
Blog › Engineering · 6 min read · Published 2026-03-11
Calculate the real cost savings and environmental impact of switching from incandescent to LED lighting.
The LED Revolution
LED (Light Emitting Diode) technology has transformed lighting economics. A standard 60W incandescent bulb can be replaced by a 9W LED that produces the same 800 lumens — an 85% reduction in energy consumption. Over the LED's 25,000-hour lifespan, a single bulb saves approximately $125 in electricity costs.
Side-by-Side Comparison
For an equivalent 800-lumen output:
- Incandescent: 60W, 1,000 hours lifespan, ~$1.00/bulb, $4.38/year (8h/day @ $0.10/kWh)
- CFL: 13W, 8,000 hours, ~$2.50/bulb, $0.95/year
- LED: 9W, 25,000 hours, ~$2.00/bulb, $0.66/year
Over 25,000 hours, LED costs ~$16.50 total vs incandescent's ~$134.50 (including 25 replacement bulbs).
The Math Behind Savings
The savings formula is straightforward:
Annual Savings = (Old_Watts − New_Watts) × Hours/day × 365 / 1000 × $/kWh × Number_of_bulbs
Example: Replacing 10 bulbs from 60W to 9W, used 8 hours/day at $0.12/kWh:
Savings = (60 − 9) × 8 × 365 / 1000 × $0.12 × 10 = $178.70/year
Environmental Impact
The average US grid produces 0.42 kg CO₂ per kWh. Those 10 LED replacements save 1,489 kWh/year, reducing CO₂ by 625 kg — equivalent to driving 1,500 fewer miles or planting 29 trees.
When to Replace
- Replace incandescent bulbs immediately — the savings justify the upfront cost within months
- Replace CFLs when they burn out — the savings over CFL are smaller
- Prioritize high-usage fixtures: kitchen, bathroom, outdoor lights used 6+ hours/day
- Look for ENERGY STAR certified LEDs for guaranteed efficiency and quality
FAQ
Do LED bulbs really last 25,000 hours?
Quality LEDs from major brands (Philips, Cree, GE) consistently achieve 25,000+ hours. At 8 hours/day, that's 8.5 years. Cheap off-brand LEDs may fail much sooner.
Do dimmable LEDs save more energy?
Yes. Dimming an LED to 50% brightness reduces power consumption by approximately 40-45%, unlike incandescent which only saves about 20% at 50% brightness.