Optimizing Compressed Air Systems: Demand Side Before Supply Side

Compressed air optimization should always begin on the demand side. Leaks, unnecessary venting, excessive operating pressures, or inefficiently operated consumers increase the actual compressed air demand. If compressed air generation is initially designed or optimized to meet this increased demand, the supply side is tailored to existing losses.

In the case of new or replacement investments, this can lead to the selection of oversized compressors. In existing systems, the subsequent elimination of leaks or other consumption reductions can result in unfavorable operating conditions, such as high idle times, inefficient part-load operation, excessively high minimum flow rates, or an unnecessarily wide pressure range.

The technical sequence should therefore be:

• Measure and optimize the demand side
• Validate savings
• Adjust the supply side to actual demand

"Demand Side" means understanding consumers' actual needs. Key metrics include flow, consumption, base load, load profiles, leakage rate, and pressure levels at the consumer’s point of use. A weekly measurement shows whether consumption remains high during downtime or production breaks. That’s often where the fastest savings opportunities lie.

Weekly measurement: Base load, production consumption, and downtime losses become apparent.

When prioritizing, it is not the number of leaks alone that matters, but rather the volume flow of the loss and the resulting costs. Large, dominant leaks should be documented and repaired first. Afterward, the area should be measured again, as smaller leaks that were previously masked may become visible.

Prioritization: The largest leaks often account for the largest share of losses. Therefore, identify, prioritize, and repair dominant leaks first.

The camera shows where a loss is occurring. Whether the measure has improved operations can only be determined through monitoring. Consumption, base load, pressure level, and specific output should be compared before and after the measure is implemented. Base load and peak load must be considered separately so that savings are not misinterpreted due to fluctuations in production.

Continuous improvement process: consumption measurement, analysis, leak detection, documentation, reporting, repair, and re-evaluation.

After adjusting for demand-side factors, the generation side can be reliably evaluated. Key performance indicators include compressor capacity, air delivery, system pressure, pressure losses, operating and idle times, and specific power. This allows the pressure band, compressor control, load distribution, and pressure losses to be optimized based on actual demand.

When compressors are sized to accommodate increased demand caused by leaks, losses are permanently factored into production. After a leak is repaired at a later date, the system may operate in unfavorable partial-load ranges. This results in increased idle times, excessively high minimum delivery rates, inefficient load/idle cycles, and a pressure band that does not match actual demand.

Monitoring ensures that the improvement achieved is not merely estimated, but actually measured. Flow, pressure, and performance data show whether repairs are effective, whether new leaks are developing, and whether production should be adjusted following demand-side optimization. Compressed air purity remains a separate but related topic for quality-critical applications such as food, pharmaceuticals, or semiconductors.