Tuesday, September 02, 2008

LED - Halogen Comparison


3-watt LED bulb on left and 20-watt Halogen spot on the right

Direct Comparison
between a
3-watt LED and a 20-watt halogen spot

One of the easiest, and IMHO the single most important way of conserving energy is to change all lighting to low wattage types of bulbs. I have addressed low wattage lighting in several posts in the past.

Up till now the only economically viable alternative to the tungsten filament was the CFL bulb. The cheap led bulbs with dozens of little LEDs were really poor quality and had a washed-out bluish tinged light not very bright and even a bit depressing. The better quality high-powered LED bulbs were available but at really high prices.

I recently bought a 3watt LED replacement bulb MR16 bulb and the cost was under €15. The colour of the light is really good and the amount of light output is reasonable.

I have included a couple of photos showing a side-by-side comparison between a standard 20-watt tungsten halogen bulb and the new 3-watt LED.

Left if the pool of light from the 20watt spot
on the right is the light from the 3watt LED

Perhaps the first thing to notice is the colour of the LED light which is close enough in tone to that of a standard bulb. The LED bulb I ordered was nominally a “warm white” I would say that is is in fact a bit cooler than 2700K more like 3500K.

The cool white LED has a very bluish light, while brighter, is very unacceptable to most of us, at least for domestic use.

The actual light output of the 3-watt LED is a good deal below that of the 20-watt halogen bulb, despite what many sellers say. I would say, at a rough guess, that the 3-watt LED is the rough equivalent of about that of a 15-watt halogen bulb.

Don't believe the hype of many of the sellers of LED bulbs - a 3-watt LED warm white bulb is no better than the equivalent of about a 15-watt halogen bulb - at best.

The LED bulb I tested works on AC or DC 12 volts. It works just fine with both conventional wound transformers and the newer electronic transformers.

I am going to try some 5-watt MR16 LED bulbs in the next few weeks and I will let you know how I get on and I will include some photos.

In the meantime, if you have some MR16 fittings and currently use 20-watt halogen spots, and would not mind a 25% or so reduction in the light, then these 3-watts LEDS would fit the bill fine.


1 comment:

Bock the Robber said...

Up to now, the colour of the LED lights has been terrible. Even though I'm a firm believer in LEDs I found it impossible to live with them and actually got rid of teh ones I installed because I hated the colours so much.

It's good to know they've improved.