What’s a VFD and why should I care?
a lighting dimmer switch, a variable frequency drive or
VFD is a device that lets you control the speed of an
electric motor. Rather than always running a fan or
pump at its top speed, a VFD (with automation) allows
the motor to slow down in proper response to a
building’s need. This saves energy!
How do I know if VFDs make sense for my
An engineering review
should be done to evaluate specific applications. In
with inlet vane controls
or piping systems with by-pass valves are often
candidates for VFDs.
In such cases, the
existing building system is already trying to control
flow – VFDs will do a
How much money
are we talking about?
For example, a typical
25-hp compartment unit fan can waste $3,500 (or more)
running faster than
needed. (To say nothing about premature wear and tear).
Using a VFD
would avoid this waste.
Assuming an engineered and installed budget of $10,000,
job would provide
2.9 year payback! (please note:
specific costs will fluctuate with site conditions)
Is that all?
Introducing VFDs shouldn’t be done without due
diligence. This would include an assessment of a
building’s existing electrical condition, including
harmonics, phase balance and general power quality.
Well, I’m interested in saving money.
What should I do?
first step, contact
your energy management partner. We’ll sit down with you
and discuss your particular needs. If VFDs make sense
for your site, we can evaluate your savings potential
and develop a budget with a payback projection. Contact
For additional information on VFDs,
follow these links: