Version vom 9. November 2014, 22:12 Uhr

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Buying a light bulb used to be easy

Buying a light bulb used to be really easy, but that changed with the arrival of energy-saving models.

It is very hard to buy a quality light bulb. I have often bought from "good" brand names and got disappointed.

Here is a feature list:

• Brightness.
  Unfortunately, the lumen values are not linear, especially from 2,000 Lumen. I don't know the maths. If you can help, please drop me a line. This is the table I have been using for reference:

Incasdencent Watt	Lumen	LED Watt	Energy-saver Watt	Halogen Watt	Col temp
40 W	400 lm	8 W
	480 lm	5 W
60 W	720 lm
80 W	1,000 lm	20 W
100 W	1,200 lm
150 W	1,700 lm
	1,900 lm	23 W			3200 K (too cold)
	2,700 lm	28 W			3000 K (a little too cold)
	2,800 lm	30 W			3000 K (a little too cold)
	3,000-3,250 lm			160 W	2800-2900 K (warm)
200 W	10,000 lm

• Color temperature. 2700K is best. 3000K might be described as "soft, warm white", but you'll notice the difference.
• Turn-on speed.
• Lifespan.
• Cycling endurance.
• Clear or frosted glass.
• Noise.
• Dimmable.
• Physical robustness.
• Operating temperature.

Compact fluorescent lamp (CFL)

I am particulary dissatisfied with compact fluorescent lamp (CFL) technology, especially after all the hype.

Its many drawbacks are:

• Expensive.
• Slow to turn on.
• Often last much shorter als advertised, due to low cycling endurance.
• Noisy. Most CFLs make a humming noise that you may notice in a quiet environment.
• Cold light colour.
• Normally not dimmable.
• The light bulb itself is also ugly.
• Contain toxic mercury (quicksilver) which complicates their disposal.
• They turn darker with time.

On the bright side, they consume very little electricity.

LED lamp

LED lamps have a few drawbacks:

• Expensive.
• Weak. I just cannot find powerful LED lamps. The ones I see around are too weak for the living room.

They win in every other category.

Halogen lamps

Advantages:

• Cheap.
• Fast to turn on.
• Bright.

Drawbacks:

• High electricity consumption compared to CFLs or LEDs.
• They lose a lot of brightness with age (see 'cooking' below).
• Dimmable, but you often get a hummy noise when dimmed from the power supply.
• They get very hot, so:
  • They tend to turn darker (they 'cook') with time.
  • If you touch one during operation, you'll get burnt.
  • Careful when cold too. Fingertip oil may make them even hotter and damage them.
• Some halogen bulbs shed a cold light (colour temp 3000 K or higher).

Fluorescent tubes

Pros:

• Cheap.
• Powerful.
• Consume little electricity.

Cons:

• Big, long.
• The starters break down often.
• Cold colour.
• Slow to turn on.
• Poor cycling endurance.
• Humming noise.
• Not dimmable.
• Brittle.