Centralised Air Station for a Gear Manufacturer in Zhejiang Cuts Running Power by 31%

The client is one of China’s larger gear manufacturers, based in Taizhou, Zhejiang Province, and uses large volumes of compressed air in production. Its supply came from 14 compressors with 1,464 kW installed power, running at about 1,300 kW in practice. The machines were spread across several separate stations with no coordinated control between them. Some were old, with high mechanical losses. The result was poor energy efficiency and no clear view of how energy was being used.

Working with a local energy-services partner, the plant built a smart centralised compressed air station that combines equipment upgrades with system-level operation:

• Base load: a new SIND TurboPure MT series centrifugal compressor.
• Trim load: SIND SILVERLUBE-VPM series variable-speed screw compressors follow demand fluctuations.
• Group control: intelligent controllers coordinate all compressors in the central station.
• Rationalisation: the most efficient original compressors were kept, and the least efficient were removed.

Centralising supply allows each compressor to run close to its best operating point. Central management also improves the quality and consistency of the delivered air. Ongoing system inspection and maintenance are included in the service scope.

Measured during the first period of trial operation:

• 1.23 million m³ of compressed air supplied using 130,000 kWh of electricity.
• 28,000 kWh saved compared with the original stations, an average energy saving of about 18%.
• Actual running power reduced from 1,300 kW to 890 kW, a drop of more than 30%.
• Better air quality through centralised, intelligent management.

The two figures measure different things: running power fell about 31% (1,300 kW to 890 kW), while the 18% figure is the share of total electricity (kWh) saved over the trial period.

Consolidating many small, uncoordinated compressors into one well-controlled central station is one of the most effective upgrades for plants with large and growing air demand.