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VFDs will transform your building

VFDs are about to radically change the carbon profile of millions of buildings in the United States.

What the heck is a VFD?

A VFD is a Variable Frequency Drive. It's a lot of complex words, but boiled down, what it really is, is a variable speed motor.

To understand why this is such a radical innovation, you really have to go back to the beginning.

In the early 1890s, Nikola Tesla invented what's known as alternating current. Alternating current is what allows electricity to get to millions of buildings over long distances in a reliable way. At the same time, Nikola Tesla invented the first alternating current motor. It's not a stretch to say without alternating current, without the alternating current motor, you pretty much wouldn't have cities as we know them today.

In order to be able to have cities filled with tall buildings, you need motors. Motors for things like elevators, things like pumps that move water up to the top of the building, compressors that turn on air conditioning systems. All of these things are made possible by alternating current motors.

The problem with the alternating current motor was that it really only had two modes, on or off.

Imagine you have, for example, a fan that powers your heating system. Imagine that fan is super, super powerful, and it blows a ton of heat into the room. You might want the room at 70 degrees, and the room is currently 65.  When we turn the fan on, very quickly it gets to 75 degrees because the fan is blowing extremely fast.

Okay, well, in order to make the room exactly 70 degrees, let's just turn the fan on and off, on and off, every 30 seconds to make the fan average speed slower and make the room 70 degrees.

This is literally how almost every motor in every building today works. It's extremely energy inefficient.

When you turn a motor on and it has to start up and then you turn it off and it slows down, you're losing a huge percentage of the energy. So what we really want is to be able to turn that motor on to 50 percent speed and leave it there, and only use 50 percent of the electricity to keep it running.

That may seem like a simple idea, but it took literally until the 1980s for really smart engineers to figure out how to make a motor that used less electricity When it was actually running at lower speeds, that is what we call a VFD.

It took then another 30 to 40 years with modern computer technology to be able to make that variable speed motor, not only energy efficient and small, but precisely controllable.

The application became even more useful in the last 10 years. when VFDs were combined with smart controls that use sensors indoors and could tell that VFD exactly how much to precisely run.

The combination of VFDs plus smart controls, which took literally almost 150  years after Nikola Tesla's original invention, are radically changing the electric profile of buildings across the country.

In fact, it's such a dynamic combination that, not only can they reduce electric usage by 30% to 50% in certain cases, but in most cases, they can actually pay for themselves in just a couple of years.

So when you think about what's making buildings green over the next 20 years, it's really this fascinating combination of 19th century discovery and 21st century technology.