Top 7 tips for saving energy with compressed air

Would you like to reduce the electrical costs associated with your compressed air system? Most likely you can. Start by determining your annual compressed air electrical costs using this formula:

Brake Power X 0.746 X Annual Operating Hours X KWH (kilowatt-hours) Cost (divided by) Motor Efficiency

NOTE: 1 CFM (cubic feet per minute) @ 100 PSIG (pound-force gauge per square inch) FOR 8760 HOURS COST $ 110.00 PER YEAR IN ELECTRICAL COST

Next … follow these 7 top tips to save energy with compressed air:

1. Fix your air leaks

If you do nothing else, follow this advice: Find and repair your compressed air leaks. Air Leaks Are The Industry’s “Biggest Loser”!

The average plant loses between 20% and 30% of its compressed air through multiple small air leaks. The money spent on labor and parts to find and repair these leaks is well worth it. Note (a 1/4-inch orifice will flow 103 cfm at 100 psig)

2. Switch to synthetic lubricants

If you are using petroleum-based lubricants, you could experience up to 8% energy savings by switching to synthetic compressor lubricants. Plus, extend equipment life and save on oil changes and disposal costs.

3. Reduce the operating pressure of the plant

If possible, reduce the overall pressure in the plant. Less pressure> Less CFM used> less energy consumed.

TIP: Reduce plant pressure 2 pounds at a time, then test operation for a minimum of 24 hours. If any equipment has problems … then increase the pressure 2 pounds until it works again without problems. For every 2 pounds of pressure reduction, you save 1% of the electrical cost to run the air compressor.

4. Check the differential pressure across the air compressor filters.

Start at the compressor cabinet filter and then check the compressor inlet filter.

Note: A dirty inlet filter can cost you 1% to 3% in additional electrical costs. Why? Because decreased air flow to the compressor inlet valve increases compression ratios, resulting in more run time.

Then check the differential pressure of the air / oil separator at full load. A new separator causes a differential pressure drop of approximately 2-3 psig. When your pressure drop reaches 8-10 psig, then it is time to change the separator elements. A dirty separator element can cost you up to 5% in additional electrical costs.

Then change the element of the control air filter. This is often overlooked, but it is still an important filter where the controls receive their air signal. A pressure drop here causes the controls to receive the lowest pressure signal by loading the compressor more and using more electricity.

5. Reduce the compressor inlet temperature

By reducing the inlet air temperature 10 ° F below 70 ° F, you save 2% on electricity use. Your profit increases up to 8% on a 30 ° F day. But increasing the inlet temperature 10 ° F above 70 ° F will cost you 2% in additional electrical usage for every 10 ° F up to 10% at 120 ° F. (Inlet temperature has little effect on lubricated screw compressors)

6. Check the differential pressure across the compressed air line filters.

The compressed air filters should be sized twice (2x) the CFM flow rate of your compressor. This will reduce your pressure drop approximately 2-3 psig and save 1% on energy costs. The elements will last twice as long (2x) and you will save on maintenance costs.

7. Know what quality of compressed air your plant needs.

The cleaner and drier the compressed air is, the more energy is consumed.

Check with your equipment manufacturer to determine the required air quality.