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CFM to kW Calculator

Use this cfm to kw calculator to quickly convert airflow into power requirements. This guide helps you understand how much electrical power your air system needs. Get accurate results with simple steps and clear formulas.

CFM to kW Converter

CFM
in. wg
%
Required Power
0.00 kW

How to Use the CFM to kW Calculator

Follow these simple steps to use the cfm to kw calculator:

  1. Step 1: Enter Airflow (CFM)
    Input the airflow value in cubic feet per minute (CFM).
  2. Step 2: Enter Pressure (Pa or inches of water)
    Add the system pressure or static pressure value.
  3. Step 3: Enter Efficiency (%)
    Input fan or system efficiency (usually between 50% and 80%).
  4. Step 4: Click Calculate
    The calculator will instantly convert CFM to kW.
  5. Step 5: Review Result
    The result shows required power in kilowatts (kW).

Tip: Always use accurate pressure and efficiency values for better results.

CFM to kW Conversion Formula

You can calculate kW manually using this formula:

kW = (CFM × Pressure) / (6356 × Efficiency)

Where:

  • CFM = Airflow (cubic feet per minute)
  • Pressure = Static pressure (in inches of water)
  • Efficiency = Fan efficiency (decimal form)

Step-by-Step Calculation Example

Example: Convert 2000 CFM to kW with Pressure = 2 inches of water and Efficiency = 70% (0.70).

Step 1: Write the formula
kW = (CFM × Pressure) / (6356 × Efficiency)

Step 2: Insert values
kW = (2000 × 2) / (6356 × 0.70)

Step 3: Multiply values
kW = 4000 / 4449.2

Step 4: Final result
kW ≈ 0.90 kW

Result: You need approximately 0.90 kW of power.

CFM to kW Conversion Chart

Assumptions: Pressure = 2 in. wg, Efficiency = 70%

CFM kW
500 0.22
1000 0.45
1500 0.67
2000 0.90
2500 1.12
3000 1.35
4000 1.80
5000 2.25

Note: Values may vary based on pressure and efficiency.

FAQs – CFM to kW Calculator

A cfm to kw calculator converts airflow into required electrical power.

No. You must include pressure and efficiency for accurate results.

Efficiency affects how much power the system uses. Lower efficiency increases kW.

Most fans operate between 60% and 75% efficiency.

You can use inches of water (in. wg) or Pascals, but keep units consistent.

It provides a close estimate. Real systems may vary due to losses.

Engineers use it in HVAC systems, ventilation design, and industrial airflow setups.

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