How Dimmers Save Energy

Do dimmers really save on energy use?

The key to answering this question is understanding how dimmers really work.

Many consumers and even a few electricians think that dimmers work by converting unused electricity to heat at the dimmer switch.

It’s true that many old rotary dimmers worked this way; they were rheostats that took the excess energy when dimmed and converted it to heat.


Today’s dimmers use a “Triac Switch”. When dimmed, these switches cut the flow of power to a light fixture up to 120 times a second.

While the circuit is switched on and off many times a second, the human eye and brain don’t register this flickering. What we see is a constant light output.

And dimmers do save. Dimming your lights an average of 50 percent can cut your electric use a whopping 40 percent over time and make your bulbs last 20 times longer!

More Dimmers Ideas and Advice:

A Quick Guide to Using Dimmers

Smart Home Wireless Remote Control Dimmers and Apps

Energy Efficient Ceiling Fans

Energy Efficient Outdoor Lighting

How to Buy LED Lighting