There’s a lighting revolution underway. You can no longer buy the old incandescent lamps that are still the symbol of a good idea . Instead there’s a bewildering array of alternatives. So which ones should you buy?
Here are the lamps I saw for sale recently at the supermarket. So many options, each with most of the fittings you could want – including the standard screw and bayonet fittings that are still standard in most older houses like mine.
They have a wide range of wattages, lumens, hours and price tags. What does is all mean?
- Watts are the amount of power used. The higher the watts, the great the energy being used.
- Lumens are the amount of light emitted. The higher the lumens, the brighter the lamp. In some places, like kitchens, we want lots of light. We may want less from our bedside lamp.
- Hours of operation differ between lamps. If a lamp lasts for many thousands of hours, you may not have to change it for a decade.
- To really understand the price tag, you need to put all of this together. A lamp that uses minimal energy, emits lots of light, and lasts for a decade is cheaper in the long run than one that uses more energy and blows quickly.
LEDs, or light emitting diodes reportedly have the lowest watts per lumen for any lights available in Australia (see the light globe conversion table at the end of this link). A key reason is that they convert electricity into light, and not heat.
I tested this using a thermal imaging camera to compare an old incandescent with a compact fluorescent and LED lamp. Each had been on for half an hour before I tested their temperature.
The hottest point on the incandescent lamp was 161 degrees Celsius. That’s a lot of electricity being converted into heat, instead of light.
The hottest point on the compact fluorescent lamp (CFL) was 134 degrees Celsius. Still pretty hot.
The hottest point on the LED lamp was 65 degrees. Most of the power is going into light, not heat.
LEDs contain less toxins than other lamps, being free of mercury, lead and phosphorous and are also fully recyclable. So there are fewer waste problems with LEDs than with other lamps. CFLs in contrast, contain mercury so it is important to recycle those.
I’m convinced. I had already swapped all of my incandescents for CFLs. Now its time to change over to LEDs. And if the quoted hours are right on these new lamps they might outlive the house.