Use an average reading for a cycling refrigerator
A resident uses a multi-day plug meter reading that averages 45 W across cooling, idle and defrost periods. They want to project that sample to 30 days.
Open CalculatorInputs and calculation
| Tool input | Value |
|---|---|
| Currency | USD |
| Power unit | W |
| Power | 45 |
| Hours per day | 24 |
| Days or equivalent sessions | 30 |
| Duty cycle (%) | 100 |
| Energy price (USD per input kWh) | 0.22 |
45 ÷ 1,000 × 24 × 30 × 100% = 32.4 kWh. 32.4 × 0.22 rounds to USD 7.13.
Tool result · USD 7.13
| Tool input | Value |
|---|---|
| Currency | USD |
| Power unit | W |
| Power | 60 |
| Hours per day | 24 |
| Days or equivalent sessions | 30 |
| Duty cycle (%) | 100 |
| Energy price (USD per input kWh) | 0.22 |
60 ÷ 1,000 × 24 × 30 × 100% = 43.2 kWh. 43.2 × 0.22 rounds to USD 9.50.
Tool result · USD 9.50
What the comparison shows
The second estimate adds 10.8 kWh. Applying a separate compressor duty factor to the average would count idle time twice.
Assumptions and limits
Set duty to 100% when power is already averaged over the full day. Repeat the measurement if room temperature or usage changes.
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