GANGPUEnvironmental Technology
Energy Saving

Fan and Pump VFD Retrofit: How the Saving Is Actually Calculated

Affinity laws, load profile measurement, harmonic limits and the metering protocol used to verify a retrofit before and after commissioning.

2026-05-086 min readGANGPU engineering team
Variable frequency drive installed on an industrial fan motor for energy saving

Affinity laws, load profile measurement, harmonic limits and the metering protocol used to verify a retrofit before and after commissioning.

What this article covers

  • Selection method for energy saving equipment under real plant conditions
  • The parameters that decide sizing: gas volume, temperature, dust or pollutant load and the outlet limit
  • Material and media choices that affect service life and running cost
  • Installation, commissioning and maintenance points that are often missed in quotation stage

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Send air volume, dust or gas composition, temperature, required outlet value and available space. Our engineers return the sizing calculation, a configuration proposal and a budget quotation. Emission and energy results always depend on your actual operating condition and the local standard in force.

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Equipment in this article

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