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Measure: Replace supply fan motor and variable frequency drive (VFD)

Building Size: 5,000 gsf
Climate Zone: Hot - Humid

Measure: Replace supply fan motor and variable frequency drive (VFD)

Building Size: 5,000 gsf
Climate Zone: Hot - Humid
Replace supply fan motor and variable frequency drive (VFD)
Measure Simple Payback (years) Approximate Capital Cost ($) Annual Energy Savings (kBtu/sf) Annual Energy Savings (kBtu/yr) Annual Cost Savings ($/sf) Annual Cost Savings ($/yr)
Replace supply fan motor and variable frequency drive (VFD) 3-4 $1,100 2.0 10,000 $0.06 $280

Description:

This measure involves replacing a facility’s supply fan motors and VFDs with premium efficiency motors and VFDs with current technology. Standard motor efficiencies have steadily increased over the last few decades due to improvements in motor design and manufacturing, and VFD efficiencies have increased greatly over the past 10 years. Minimum motor efficiencies prescribed in building energy codes and federal regulations are frequently increased to keep pace with these improved efficiencies.

Special Considerations

  • Most facilities do not consider upgrading motors or VFDs with higher efficiency models until the existing motors or VFDs need to be replaced due to failure or system replacement/reconfiguration. However, it may be worth replacing large, old VFD/motor combinations that operate frequently with more efficient models even before failure.

Estimates for this measure come from the Department of Energy's Advanced Energy Retrofit Guide.