Monday 30 March 2009

4. Summary - Lamp Type Pros & Cons

Comparison between different lamp types:

I. INCANDESCENT LAMPS

Models:
* Standard A-bulbs and T-bulbs
* Decorative (globe, flame, tinted etc)
* Reflector & PAR

Advantages:
+ Bright point light source
+ Good quality and performance
+ Natural golden-white light
+ Continuous spectrum
+ Highest colour rendering (CRI 100)
+ Lights up immediately
+ Can be used at both freezing and hot temperatures
+ Full compatibility with existing luminaires
+ Fully dimmable on any dimmer
+ Light gets warmer and more candle-like when dimmed
+ Highest Power Factor (1.0)
+ Contains no mercury (and no lead solder after 2006)
+ Easy to produce, use and recycle
+ Low purchase price

Disadvantages:
- More heat than light
- Short lifetime, 1000 hours (Long Life lamps 2500-7500 hrs, at reduction in output)
- Sensitive to voltage fluctuations
- Sensitive to vibrations (except Rough Service bulbs)


II. HALOGEN LAMPS

Models:
* Low voltage halogen minibulbs for spotlights
* Halogen minitubes for floodlights
* Halogen retrofit lamps with outer bulb and scew base
* Halogen retrofit reflector and PAR lamps
* Halogen retrofit Energy Saver bulbs & reflector lamps (new)
* Halogen retrofit bulbs with xenon gas filling (new)
* Halogen retrofit bulbs with IR coating and integrated transformers (new)

Advantages:
+ 10-50% more light than incandescent
+ Bright point light source
+ Good quality and performance
+ Continuous spectrum
+ Highest colour rendering (CRI 100)
+ Sunny white light
+ Fully dimmable on any dimmer
+ Gets warmer when dimmed
+ Full compatibility with existing luminaires
+ Light up immediately
+ Work as well in low as in high temperatures
+ Highest Power Factor (1.0)
+ Do not lose output with age
+ Contain no mercury or other toxic chemicals

Disadvantages:
- Low to medium low efficiency
- Risks due to high operating temperature
- Models with clear bulb or tube may be very glaring
- Medium short lifetime (2000 - 3000 hours, some reflector lamps up to 6000 h)


III. COMPACT FLUORESCENT LAMPS (CFLs)

Models:
* Tubes without integrated ballsts
* Retrofit tubes with integrated ballasts
* Retrofit spiral tubes
* Retrofit A-bulbs with outer envelope
* Retrofit globes & decorative with outer envelope
* Retrofit reflectorlamps

Advantages:
+ "Up to 80%" (in reality closer to 50%) more light than an incandescent
+ Long lifetime (6 000-15 000 hrs, with diminishing output)
+ Available with warm or cool light

Disadvantages:
- No bright point lighting
- Most models still have unnatural colour
- Suboptimal colour rendering (CRI 82-85)
- Naked tubes often glaring
- Relatively long starting and warm up time
- Lower Power Factor (often around 0.5)
- Sensitive to heat; poor function in closed luminaires
- Many have poor performance in cool temperatures
- May be sensitive to moisture
- May be sensitive to rapid on-off switching
- Often not dimmable (those that are often expensive)
- Dimming makes the light cooler/greyer, not warmer
- Too large for some luminaires
- Do perform well in reflector luminaires

- Some require specific burning position
- Higher production, transportation and recycling costs
- Contain small amounts of mercury (2-5 mg)
- Bare tubes may emit a little UV


IV. LIGHT EMITTING DIODES (LEDs)

Models:
* Reflector lamps (diodes stuck in a reflector lamp)

* Retrofit standard bulbs (diodes stuck on a stick and placed in a bulb).
* Decorative (tube lights etc)

Advantages:
+ Good efficacy (high output per watt)
+ Extremely long life (unless overheated)
+ Light up instantly
+ Warm, cool or coloured light
+ Versatile due to very small size
+ Not sensitive to vibrations, power spikes or rapid cycling

+ Not sensitive to cold
+ Give off less heat than other lamps, can be touched
+ Simpler to produce and recycle than CFLs
+ Contain no mercury


Disadvantages:
- Most common as low-watt lamps*

- Give light only in one direction, in narrow beam
- More or less unnatural light colour*
- Unstable colour, warm-white LEDs shift over time
- Mediocre to good colour rendering*
- Sensitive to heat
- Lower Power Factor than incandescent*
- Expensive*

* Under improvement


References:
EU consultants' Technical Briefing (italicised points)
Philips Lighting
OSRAM
Havells-Sylvania
GE Lighting
MEGAMAN
Aura Light

5 comments:

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  2. jack, that's quite enough of your spamming!

    I might have let one of your links stay put but posting the same link to the product you're selling all over this blog under the guise of feedback is not acceptable. Now I have to remove all your 'comments'.

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