Advanced air handler energy analysis for airflow-driven fan systems. Review electrical demand, loads, and schedules. Export tables, charts, and summaries for faster engineering decisions.
| Airflow | Static Pressure | Fan Eff. | Motor Eff. | Connected Power | Annual Energy | Total Annual Cost |
|---|---|---|---|---|---|---|
| 12000 CFM | 2.50 in.w.g. | 65% | 92% | 5.8857 kW | 18010.33 kWh | 3157.10 |
| 18000 CFM | 3.00 in.w.g. | 68% | 93% | 10.0180 kW | 30655.15 kWh | 5373.67 |
| 24000 CFM | 3.20 in.w.g. | 70% | 94% | 13.6935 kW | 41902.21 kWh | 7345.21 |
1) Air horsepower
Air horsepower = (Airflow in CFM × Static Pressure in in.w.g.) / 6356
2) Brake horsepower
Brake horsepower = Air horsepower / Fan efficiency
3) Motor input power
Electrical kW = (Brake horsepower × 0.745699872) / Motor efficiency
4) Annual energy use
Annual kWh = Electrical kW × Load factor × Hours per day × Days per year
5) Annual energy cost
Annual energy cost = Annual kWh × Electricity rate
6) Sensible thermal load
Sensible load = 1.08 × Airflow in CFM × Temperature difference in F
7) Current estimate
Three phase current = kW × 1000 / (√3 × Voltage × Power factor)
This calculator converts metric and imperial inputs automatically, then reports fan power, energy use, cost, specific fan power, and sensible air-side load.
For better estimates, use measured airflow, verified static pressure, and nameplate efficiency data. If conditions change by season, run several cases and compare the outputs.
Air handler energy use depends mainly on airflow, total static pressure, fan efficiency, and motor efficiency. When airflow or resistance increases, required fan power also increases. Dirty filters, restrictive coils, closed dampers, and poor duct layouts can all raise electrical demand and annual operating cost.
This calculator focuses on fan-side electrical energy and sensible air-side load. The power section estimates the motor input needed to move the selected airflow against the entered static pressure. The load section estimates sensible thermal capacity from airflow and temperature difference. These values answer different engineering questions.
Use the power outputs for budgeting, energy studies, and operating comparisons. Use the load outputs for quick air-side checks, coil review, and commissioning discussion. The specific fan power values help compare systems of different sizes and can reveal when a system is becoming less efficient over time.
The graph adds a simple sensitivity study by changing airflow while keeping other assumptions fixed. That helps during design revisions, retrofit evaluations, and commissioning adjustments.
It estimates fan horsepower, electrical input power, annual energy use, annual cost, sensible thermal load, specific fan power, and optional current draw for an air handler.
It estimates sensible air-side capacity from airflow and temperature difference. It does not replace a full coil selection or full psychrometric analysis.
Load factor converts connected power into average operating power. This helps annual energy reflect real schedules and part-load operation instead of constant full-load running.
Enter the total system or external static pressure used for fan energy estimation. Keep the value consistent with your airflow measurement method and design basis.
Use m3/h for airflow, Pa for pressure, and C for temperature difference. The calculator converts the values automatically before applying the formulas.
It is an estimate based on input kW, voltage, phase, and power factor. Measured current can differ because of controls and actual motor loading.
Specific fan power helps compare systems of different sizes. Lower values usually mean less electrical input per unit of delivered airflow.
Yes. It is useful for comparing filter upgrades, duct changes, motor replacements, and schedule adjustments before and after improvements.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.