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:
Unfortunately, the lumen values are not linear (they do not increase proportional to the current flow), 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 Info source 40 W 450 lm 5 W 10 W 1 60 W 800 lm 10 W 15 W 1 75 W 1100 lm 14 W 20 W 1 100 W 1,200 lm 150 W 1,700 lm 1,900 lm 23 W 2,700 lm 28 W 2,800 lm 30 W 3,000-3,250 lm 160 W 200 W 10,000 lm
Info source 1: El País, La (ardua) tarea de elegir la bombilla perfecta y ahorrar.
- Color temperature.
2700K is best, it yields a yellowish light comparable to the traditional incasdencent light bulbs with a tungsten (wolfram) filament.
3000K might be described as "soft, warm white", but it's a little too cold and you'll notice the difference. Anything over 3000K will be too cold, and the light will turn blueish.
- Turn-on speed.
- Cycling endurance.
- Clear or frosted glass.
- 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:
- 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 lamps have a few drawbacks:
- 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.
- Fast to turn on.
- 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).
- Consume little electricity.
- Big, long.
- The starters break down often.
- Cold colour.
- Slow to turn on.
- Poor cycling endurance.
- Humming noise.
- Not dimmable.