In our previous article, we explained what a Grade 1 Energy-Efficient Compressed Air Station is and why more and more companies are pursuing this certification.
But what many plant managers are really asking is:
"Does our plant have what it takes to achieve Grade 1 certification?"
“Is my plant actually a good fit for this?”
In practice, many companies assume that simply replacing an existing compressor with a high-efficiency model is enough to achieve Grade 1 performance.
In reality, the evaluation focuses on the overall efficiency of the entire compressed air system under actual operating conditions. It considers not only compressors, but also air treatment equipment, cooling systems, control systems, metering systems, heat recovery, and day-to-day operational management.
In other words, Grade 1 certification is not determined by how advanced a single piece of equipment is. It reflects how efficiently the entire system performs.
Before formally launching a retrofit or certification application, it's worth running a quick self-check using the three steps below.
Step 1: Determine Your Eligibility
First, determine whether your compressed air station meets the basic requirements for a Grade 1 energy-efficiency assessment.
As per the relevant standards, a compressed air station participating in the energy efficiency evaluation should generally meet the following conditions:
✅ The air compressor is motor-driven
✅ Rated power of a single unit is no less than 18.5 kW
✅ Air delivery is no less than 4 m³/min
✅ Discharge pressure is within the range of 0.25–1.6 MPa
✅ Total operating power of the unit(s) is no less than 37 kW
If your station meets the basic requirements, consider whether any of the following situations apply:
✅ Multiple compressors operate together without coordinated control
✅ Air demand is relatively stable and continuous
✅ System pressure is higher than necessary or experiences noticeable fluctuations
✅ The air consumption, power consumption, and pressure losses of air treatment equipment are not clearly monitored
✅ Electricity is a major operating expense, but no compressed-air energy-performance benchmark has been established
✅ Equipment has been in service for many years
✅ The company has clear energy-saving and cost-reduction objectives
In general, the more items that apply, the greater the potential for system optimization and the stronger the business case for developing a Grade 1 Energy-Efficient Compressed Air Station.
Step 2: Evaluate Your Equipment and System Design
Many companies assume that a Grade 1 Energy-Efficient Compressed Air Station simply requires a Grade 1 air compressor.
In reality, the evaluation is based on the performance of the entire system.
Whether the system uses rotary screw, centrifugal, or reciprocating compressors, it may qualify for Grade 1 certification as long as the required system-level performance targets are achieved.
We recommend focusing on the following three areas.
① Are Individual Compressor Efficiencies Appropriate?
For positive displacement air compressors, it is advisable to prioritize high-efficiency units that meet the requirements of GB 19153.
When selecting equipment, companies should look beyond performance at rated conditions and also consider:
- Whether typical air demand matches the capacity of the unit(s)
- Whether good efficiency is maintained at low load
- Whether the equipment combination can cover day-to-day load variation
- Whether the discharge pressure matches actual production requirements
If lower-efficiency equipment is still present at the station, this does not necessarily rule out Grade 1 energy efficiency evaluation, but it will often make it noticeably harder for the system to reach Grade 1 efficiency.
For this reason, before starting an assessment, it is advisable to first check equipment nameplates, energy efficiency test reports, or procurement records to understand the efficiency level of existing equipment.
② Is the Air Treatment System Properly Designed?
In many compressed air systems, the downstream treatment system also affects the efficiency of the entire station.
For example:
- Heatless desiccant dryers typically consume a significant amount of compressed air for regeneration.
- Micro-heated desiccant dryers also require compressed air and electrical energy during the regeneration process.
In some cases, 10 to 20 Nm³ of compressed air may be consumed by the drying process for every 100 Nm³ produced.
This loss directly affects overall system efficiency, and is one of the key reasons many air stations struggle to reach Grade 1 energy efficiency.
For this reason, when selecting equipment, companies should compare:
✅ Regeneration air consumption
✅ Heating and blower power consumption
✅ Pressure drop across dryers and filters
✅ Treatment capacity and dew point stability under actual operating conditions
In addition, companies with a Grade 1 energy efficiency goal may also want to focus on:
✅ Blower-purge desiccant dryers
✅ Heat-of-compression (HOC) desiccant dryers
✅ Other low-purge or zero-purge drying solutions
By reducing energy consumption in downstream treatment, overall system operating efficiency can be improved.
③ Do You Have Intelligent Control and System Optimization Capabilities?
In real-world conditions, a company's air demand is often in a state of constant change.
Without coordinated system control, facilities often experience:
- Pressure fluctuations
- Frequent load/unload cycling
- Multiple compressors operating simultaneously at inefficient load points
For this reason, a high-efficiency air station generally needs to have:
✅ Centralized monitoring
✅ Multi-compressor coordination
✅ Automatic load optimization
✅ Intelligent supervisory control
For facilities with significant demand fluctuations, technologies such as variable-speed drives (VSDs), multi-compressor control systems, and intelligent optimization platforms can help match air supply to actual demand in real time, reducing energy waste and ensuring the system operates within its most efficient range.
Step 3: Evaluate Your Site Conditions
Many companies have efficient equipment and meet the basic capacity requirements, yet still encounter challenges during the evaluation process.
In many cases, the root cause lies in the site's operational foundations and data infrastructure.
① Do You Have a Metering and Monitoring System in Place?
A reliable metering and monitoring system is one of the most important prerequisites for achieving Grade 1 certification.
Energy efficiency assessments are based on measured operating data, not assumptions or experience.
At a minimum, companies need to be able to track:
- Station power consumption
- Compressed air production
- System pressure
- Temperature and operating status
- Energy consumption of key equipment
Continuous monitoring and data recording are essential for understanding system performance, evaluating the balance between air supply and demand, and accurately calculating overall system efficiency.
If a comprehensive monitoring system is not yet in place, establishing one should be a priority.
② Are Operating Conditions Stable and Representative?
Energy efficiency assessments must be conducted under representative operating conditions.
If a company is currently in:
- The ramp-up phase of a new project
- A capacity ramp-up phase
- A phase with significant order fluctuation
- A state of prolonged low-load operation
Then the test results may not accurately reflect the system's actual energy efficiency.
For the most accurate and objective results, evaluations should be conducted when production conditions are stable and representative of normal operations.
Quick Self-Check: How Many Boxes Does Your Plant Tick?
✅ Your compressed air station meets the minimum evaluation requirements
✅ Production air pressure, flow demand, and air quality requirements have been clearly defined
✅ Compressor efficiency is at a high level
✅ Drying-system purge losses and energy consumption are well controlled
✅ Intelligent multi-compressor control is in place
✅ A metering and monitoring system has been established
✅ Production demand remains stable over the long term
If you answered “Yes” to most of these questions, your facility likely has a strong foundation for pursuing a Grade 1 Energy-Efficient Compressed Air Station.
Key Takeaways
The core of a Grade 1 Energy Efficiency Air Station is not simply swapping in one high-efficiency piece of equipment.
Its essence lies in achieving system-wide optimization across equipment efficiency, control strategy, downstream treatment, metering and monitoring, heat utilization, and operational management.
Companies can use the following path to quickly assess their own readiness:
Meet the Capacity Requirements → Improve Equipment Efficiency → Optimize the Air Treatment System → Implement Intelligent Control → Establish a Robust Metering System → Ensure Stable Operating Conditions
Once these conditions are met, a company is generally ready to move into the formal evaluation stage for a Grade 1 Energy Efficiency Air Station.
If some conditions are not yet met, there's no need to worry. In upcoming articles, we'll continue to break down the equipment retrofits, efficiency-improvement pathways, ROI analysis, and application process involved in building a Grade 1 Energy Efficiency Air Station, to help companies find the upgrade plan that best fits them.