Do dimmer switches save energy?

Lighting has become so much more efficient in the last few decades. We have moved from old fashioned incandescent bulbs to CFL and LED bulbs, which can save up to 90% on your lighting costs, but people know less about their dimmer switches. How do they work, and do they actually save you money?

What is a dimmer switch?

Dimmer switches allow you to alter the amount of light produced from a lightbulb, without the need for installing complex wiring. They mean you can produce mood lighting, which can have a dramatic impact on the look and feel of a room. Different lighting can create a completely different atmosphere without the need to move any furniture around a room or redecorating and all this can be achieved with a simple dimmer switch.

Does a dimmer cut your energy use?

Dimmers have been around for a very long time, almost as long as the light bulb itself. In the early years, they worked by adding resistance to the circuit, which turned the energy into heat rather than light. This  does not reduce the amount of electricity being used, it just changes the amount being turned into light. This has the added problem of the excess heat, which could potentially be quite dangerous!

Modern dimmers don’t work that way. There are several different variations, but effectively modern dimmer switches cut the supply on and off rapidly at hundreds of times per second – something called a TRIAC switch. This reduces the amount of power reaching the bulb, reducing the brightness. This does reduce the overall amount of power being used and therefore you could call them more efficient.

Better to dim or not to dim?

With LED lights the effect of dimming compared to power use is fairly linear. However, dimming incandescent is actually less efficient than using a lower wattage of bulb. For example, a 60W bulb dimmed to the brightness of a 40W bulb will use more energy than a 40W bulb on maximum. The light will also tend to be ‘warmer’ in colour.

What are the benefits of dimming?

Using a dimmer can actually help prolong the life of your bulbs. This is because bulbs running at lower power get put under less stress as there is less heat being emitted.This is why some of those famous bulbs you see on the internet that are still running after 100 years tend to be at very low levels – they would have burnt out long ago if they were at maximum output.

>>> Choosing the right LED lighting <<<

Dimming is really useful because it lets you alter the light levels subtly, rather than just having ‘on’ and ‘off’. It really adds another dimension to your home’s lighting. So don’t be afraid to get dimmers for your home. They won’t be wasting you energy – in fact they should save you a little and prolong the life of your bulbs.