Compare two heat-pump operating conditions
The same hot-water draw can require different electrical input as a heat pump’s operating performance changes. Compare illustrative COP values of 2 and 4 for the same delivered heat.
Open CalculatorInputs and calculation
| Tool input | Value |
|---|---|
| Currency | USD |
| Volume or billing unit | liters |
| Volume (L) | 100 |
| Temperature rise (°C) | 40 |
| Heating method | Heat pump |
| Coefficient of performance (COP) | 2 |
| Energy price (USD per input kWh) | 0.3 |
| Water price (USD/L) | 0 |
Heat delivered = 100 × 40 × 0.001163 kWh. Divide by 2 to get about 2.326 input kWh. Multiply input energy by 0.3, add 100 × 0 for water, then round to USD 0.70.
Tool result · USD 0.70
| Tool input | Value |
|---|---|
| Currency | USD |
| Volume or billing unit | liters |
| Volume (L) | 100 |
| Temperature rise (°C) | 40 |
| Heating method | Heat pump |
| Coefficient of performance (COP) | 4 |
| Energy price (USD per input kWh) | 0.3 |
| Water price (USD/L) | 0 |
Heat delivered = 100 × 40 × 0.001163 kWh. Divide by 4 to get about 1.163 input kWh. Multiply input energy by 0.3, add 100 × 0 for water, then round to USD 0.35.
Tool result · USD 0.35
What the comparison shows
Doubling COP halves modeled electrical input for the same 4.652 kWh of delivered heat. COP is a ratio, so enter 2 or 4 directly.
Assumptions and limits
Use a representative operating COP. Ambient temperature and backup resistance operation can change seasonal performance.
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