What is specific power?
Specific power (unit: kW / m³/min) is a key performance indicator for air compressors, representing the electrical power (in kilowatts) required to deliver 1 cubic meter of free air per minute. The lower this value, the higher the equipment’s energy efficiency.
Key factors affecting specific power
- Compression methods (such as screw, reciprocating, and centrifugal)
- Intake air temperature and humidity
- Exhaust pressure (0.7MPa, common operating conditions such as 0.8 MPa)
- Cooling efficiency and system compatibility
Reference range for specific power
Under standard operating conditions (suction pressure 0. 1MPa, temperature 20°C, relative humidity 60%, exhaust pressure 0. 7MPa) Down:
- Class 1 Energy-Efficient Screw Air Compressor: ≤6.5 kW / m³/min
- Class II energy-efficient screw air compressor: 6.5–7.2 kW / m³/min
- Conventional reciprocating air compressors: typically above 7. 5 kW / m³/min
How to calculate the power requirement of an air compressor?
If the displacement is known (m³/min) and the measured or nominal specific power (kW / m³/min), the input power can be estimated using the following formula:
Power (kW) = Displacement (m³/min) × Specific power (kW / m³/min）
For example: displacement is 1 m³/min, with a specific power of 6. 8 kW / m³/min Then the theoretical input power is approximately 6. 8 kW.