Compare two outlet targets for a fixed draw
A household budgets for a 100 L draw at an illustrative 45°C versus 55°C outlet with a 15°C inlet. The comparison describes heat needed at two targets.
Open CalculatorInputs and calculation
| Tool input | Value |
|---|---|
| Currency | USD |
| Volume or billing unit | liters |
| Volume (L) | 100 |
| Temperature rise (°C) | 30 |
| Heating method | Electric resistance |
| Efficiency (%) | 100 |
| Energy price (USD per input kWh) | 0.25 |
| Water price (USD/L) | 0 |
Heat delivered = 100 × 30 × 0.001163 kWh. Divide by 1 to get about 3.489 input kWh. Multiply input energy by 0.25, add 100 × 0 for water, then round to USD 0.87.
Tool result · USD 0.87
| Tool input | Value |
|---|---|
| Currency | USD |
| Volume or billing unit | liters |
| Volume (L) | 100 |
| Temperature rise (°C) | 40 |
| Heating method | Electric resistance |
| Efficiency (%) | 100 |
| Energy price (USD per input kWh) | 0.25 |
| Water price (USD/L) | 0 |
Heat delivered = 100 × 40 × 0.001163 kWh. Divide by 1 to get about 4.652 input kWh. Multiply input energy by 0.25, add 100 × 0 for water, then round to USD 1.16.
Tool result · USD 1.16
What the comparison shows
Ten more degrees of rise add 1.163 kWh for this volume. The comparison holds hot supply volume fixed.
Assumptions and limits
This is a calculation, not advice on tank storage settings or safe tap temperatures. A mixing valve can change the effective draw from the heater.