Avoid repeated reheats in an electric kettle
Three four-minute heating sessions in a 1,800 W office kettle total 12 powered minutes a day. Compare that routine with one four-minute session, assuming the same starting conditions for each session.
Open CalculatorInputs and calculation
| Tool input | Value |
|---|---|
| Currency | USD |
| Power unit | W |
| Power | 1800 |
| Hours per day | 0.2 |
| Days or equivalent sessions | 30 |
| Duty cycle (%) | 100 |
| Energy price (USD per input kWh) | 0.25 |
| Alternative power (W) | 1800 |
| Alternative hours per day | 0.0666666666667 |
| Alternative duty cycle (%) | 100 |
Baseline: 1800 ÷ 1,000 × 0.2 × 30 × 100% = 10.8 kWh. Alternative: 1800 ÷ 1,000 × (4/60) × 30 × 100% = 3.6 kWh. Multiply both by 0.25; the baseline minus the alternative is USD 1.80.
Modeled difference · USD 1.80
What the comparison shows
The electricity estimate changes from 2.70 to 0.90. If each boil fills and discards the same 0.7 L, two avoided fills daily also avoid 42 L in 30 days.
Assumptions and limits
This assumes each powered session lasts four minutes at full draw. A different water fill or starting temperature changes runtime.