Compare an incandescent lamp with a comparable LED
A resident is replacing a reading lamp and wants to estimate the difference for two bulbs with similar light output. They use the bulbs’ electrical ratings.
Open CalculatorInputs and calculation
| Tool input | Value |
|---|---|
| Currency | USD |
| Power unit | W |
| Power | 60 |
| Hours per day | 5 |
| Days or equivalent sessions | 30 |
| Duty cycle (%) | 100 |
| Energy price (USD per input kWh) | 0.25 |
| Alternative power (W) | 9 |
| Alternative hours per day | 5 |
| Alternative duty cycle (%) | 100 |
Baseline: 60 ÷ 1,000 × 5 × 30 × 100% = 9 kWh. Alternative: 9 ÷ 1,000 × 5 × 30 × 100% = 1.35 kWh. Multiply both by 0.25; the baseline minus the alternative is USD 1.91.
Modeled difference · USD 1.91
What the comparison shows
At the same schedule the LED reduces draw by 51 W. The 7.65 kWh change is worth about 1.91 at the sample rate.
Assumptions and limits
The comparison covers energy only. Check brightness, dimmer compatibility and purchase price separately.