Variable Frequency Drives for Fans, Pumps and Compressors
Match motor speed to demand on fans, pumps, compressors and AHUs.
How much energy does a VFD save?
A variable frequency drive (VFD) slows a motor to match actual demand instead of running it at full speed. On fans and pumps, power falls with the cube of speed, so running 20% slower uses roughly half the energy. VFDs also soft-start motors and lower peak demand.
What is Variable Frequency Drives?
Most fans and pumps are sized for the hottest day or the highest flow. The rest of the year they run at full speed while dampers or valves throw the extra away. A VFD changes motor speed electronically instead.
The affinity laws in plain language: flow follows speed, pressure follows speed squared, and power follows speed cubed. At 80% speed a fan needs about 0.8 × 0.8 × 0.8 = 51% of full power. That is roughly a 50% energy saving for a 20% speed reduction.
How does it lower your bill?
- Cube-law savings on variable-torque loads such as fans, pumps and cooling-tower fans.
- Soft start reduces inrush current, mechanical stress and belt wear.
- Lower peak kW, which reduces the monthly demand charge.
- Better control of pressure, flow and temperature.
Typical savings
Typically 20–50% of the motor's energy on variable-torque loads (typical, varies by facility and duty cycle).
Typical, varies by facility. Confirmed through an on-site audit and metered M&V.
Ideal facilities
- Air handlers and supply/return fans
- Chilled and condenser water pumps
- Cooling-tower fans
- Process pumps and blowers
- Compressors with variable demand
Utility capital pays for part of the upgrade
VFDs on qualifying HVAC fans and pumps are commonly eligible for NV Energy prescriptive or custom incentives. We document motor nameplates, run hours and control sequences for the application.
- We identify every eligible NV Energy prescriptive and custom incentive.
- We stack lighting with controls to raise the incentive 20–50%.
- We prepare and submit the application, then verify savings under IPMVP.
Measured under IPMVP, monitored 24/7/365
We follow the International Performance Measurement and Verification Protocol (IPMVP). Before work starts we set a metered or engineering baseline. After installation we measure the same loads and adjust for weather, occupancy and operating hours. The difference is your verified savings, and it is reported in kWh, kW and dollars.
About Virtual Energy ManagementAudit
On-site survey of lighting, HVAC, refrigeration, motors and metering. We document baselines and operating hours.
Engineering & Financial Model
Measure-by-measure design with kWh, kW, cost, incentive, SIR, IRR and payback.
Incentive Application
We prepare and submit NV Energy prescriptive and custom applications and track approval.
Installation
Licensed crews install on your schedule, nights and weekends included, with minimal disruption.
M&V / VEM
IPMVP-compliant verification and 24/7/365 Virtual Energy Management keep savings in place.
Estimate savings: Variable Frequency Drives (VFDs)
Adjust the inputs for a planning estimate. The full calculator adds incentives, payback, CO2 and a 10-year view.
Assumes $0.10/kWh and $12/kW-month. Change rates in the full calculator.
Planning estimate only. Actual savings and incentives are confirmed through an on-site audit and utility program approval.
Related solutions
Frequently asked questions
Is the affinity law real or a sales claim?
It is standard engineering physics for centrifugal fans and pumps. Real savings depend on the system curve and run hours, so we model each motor.
Can a VFD be added to an existing motor?
Often yes, if the motor is inverter-rated or suitable for drive duty. We check nameplates and insulation class during the audit.
Do VFDs qualify for NV Energy rebates?
Many HVAC fan and pump VFDs qualify. Amounts depend on the current program year and motor size.
What about harmonics?
We specify drives with appropriate filtering, and we can meter power quality before and after installation.
How do VFDs work with vibration sensors?
Sensors confirm the motor runs smoothly at new speeds and flag resonance or bearing wear early.
Turn Your Overhead Into Net Profit.
Book a no-pressure consultation with a veteran energy consultant. We will show you the savings, the incentive and the payback before you commit.
Every month you wait is money lost to inefficiency. Incentive funding is limited per program year.