LEDs use 80–90% less electricity than old incandescent bulbs at the same brightness. But when does switching actually pay off? It depends on operating hours, the electricity price and the LED cost. Our calculator shows you how many months it takes for the savings to exceed the purchase price.
Step by Step: How to Use the LED Savings Calculator
- Enter the incandescent wattage: For example 60W (old incandescent bulb).
- Enter the LED equivalent: A 60W incandescent is replaced by an ~8–9W LED.
- Enter daily burning hours: For example 4 hours/day in the living room.
- Enter the electricity price: Current rate per kWh (2025 approx. £0.29–0.35/kWh).
- Enter the LED price: For example £5.50 for a 9W LED. The result shows annual savings and payback period.
Practical Examples
Living room ceiling light: 60W → 9W LED. Burning time 4h/day = 1,460h/year. Saving: (60−9)W × 1,460h / 1,000 × £0.31 = £23.08/year. LED cost £5.50 → payback: 2.9 months!
Kitchen with 5 halogen spots at 50W each: Total 250W → 5 LEDs at 5W = 25W. 3h daily: saving = 225W × 1,095h × £0.31 = £76.40/year. 5 LEDs at £4 each = £20 purchase cost → payback: 3 months.
Outdoor light with a 100W bulb: LED 12W, 6h/night every day. Saving: 88W × 2,190h × £0.31 = £59.75/year. Payback of an £8 LED: 7 weeks.
LED Savings Quick Reference
- 40W incandescent → 5W LED: 87.5% saving
- 60W incandescent → 8W LED: 86.7% saving
- 100W incandescent → 12W LED: 88% saving
- 50W halogen → 7W LED: 86% saving
At £0.31/kWh and 4h/day: annual saving per 60W bulb ≈ £23
Frequently Asked Questions (FAQ)
Are LEDs worth it in rarely used rooms?
With less than 1h/day usage, annual savings fall significantly. For a storage room used 15 min/day with an old 40W bulb: saving approx. £4/year with LED cost £4 → payback 1 year. Still worthwhile, since an LED lasts 15,000–25,000 hours.
How long do LED bulbs really last?
Quality LEDs last 15,000–25,000 operating hours. At 4h/day: 10–17 years. Incandescent bulbs last around 1,000 hours = 9 months at 4h/day. With LEDs, replacement is rarely needed.
Is it true that LED light is inferior?
Modern LEDs achieve colour rendering Ra > 90 (very good) and are available in warm white (2700K), neutral white (4000K) and daylight (5500K). Quality LEDs are equal to or better than halogen in terms of light quality.
