Prior to the Augwind 's storage system installation, the compressed air consumption at the plant was very volatile: flow rates ranged between:
17300m3/h - 9000m3/h
Occasionally, when high flow occurs for a long time, the working pressure in some areas would drop below 5.5 bar and cause operational problems. The customer has an advanced compressor station with 7 identical compressors in size, one with variable speed drive. The compressors are operated by a central controller when the target pressure is set to 7 bar.
The 1st diagram describes measurements in the representative period before adding the underground storage system for the customer
Based on the data presented, the company conducted a comprehensive survey that included compressor power monitoring, pressure and power in different areas of the plant. A simulation was performed that simulated the factory work with large accumulators at different locations in the factory and together with the customer we considered different alternatives.
The connected techno-economic solution was the inclusion of 5 underground receivers with total volume of 150m3 installed near the compressor farm and various plant sites to overcome pressure drops in some areas - the so-called "end-of-line tank". Before installation, average power consumption throughout the year (including weekends and holidays) was 615 kWh with an average working pressure of 7 bar.
The 2nd diagram presents the measurements after the system was installed. In practice, after the installation, the power consumption dropped to 518 kWh throughout the year and the average pressure dropped to 6.4 bar.