Matching Air Quality to Demand Needs

Depending on the intended final use, compressed air needs to meet certain quality requirements with regards to contaminants and dryness. As the air quality requirements increase, so do the capital and operational – including energy – costs of compressed air system. Requirements for lubricant–free air is often of particular importance, as such air can either be produced with using lubricant–free compressors or be removed afterwards with the use of appropriate separation equipment. Lubricant-free rotary screw and reciprocating compressors usually have higher first costs, lower efficiency, and higher maintenance costs than lubricant-injected compressors. However, the additional separation and filtration equipment required by lubricant-injected compressors will cause some reduction in efficiency, particularly if systems are not properly maintained. By considering these factors, along with, and in light of, quality tolerance levels of the end users, an optimum solution can be obtained.

Development Status Products

Matching Air Quality to Demand NeedsCosts & Benefits

Parent Process: Compressed Air Systems
Energy Savings Potential

This measure is estimated to offer following improvement potentials:
• 8% for low efficiency base cases;
• 6% for medium efficiency base cases;
• 2% for high efficiency base cases.

Electrical and primary energy savings potential of this technology for different countries is estimated as following (UNIDO, 2010):

  Final (GWh/y) Primary (TJ/y)
US 1016 11153
Canada 268 3340
EU 889 8351
Thailand 115 1152
Vietnam 51 736
brazil 177 1973
CO2 Emission Reduction Potential

Total emisson reduction potential, as kt CO2/y for different countries are estimated as (UNIDO, 2010): 

US 612
Canada 134
EU 388
Thailand 60
Vietnam 25
brazil 26


Estimated typical capital costs of this measure for different system sizes (S) are:
• US $3500  for S < 37 kW;
• US $7500 for 37 kW < S < 75 kW;
• US $10000 for 75 kW < S < 150 kW;
• US $20000 for 150 kW < S < 375 kW;
• US $25000 for 375 kW < S < 745 kW; (UNIDO, 2010)

Cost of conserved energy, expressed as US $/MWh-saved, in different countries are estimated as following (UNIDO, 2010):

US 136.6
Canada 140.6
EU 154.9
Thailand 111.6
Vietnam 110.1
brazil 107.7

Parent Process:
Energy Savings Potential
CO2 Emission Reduction Potential



Matching Air Quality to Demand Needs Publications

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