Everyone is aware of the change to LED lighting from incandescent and compact fluorescent bulbs. There are many benefits in making the switchover:
- Lower energy consumption – about 90% LESS than incandescent, and about half of CFL (compact
- fluorescent lighting).
- Longer lasting – with some LED’s rated for up to 50,000 hours, they will outlast their
- predecessors by 2 to 20 times!
- Many new light quality choices – the spectrum is wide open…
The drawbacks are few, but the new choices mean the consumer needs to learn new “decision information” so that the choices are made with understanding.
LED (pronounced ELL-EEE-DEE) stands for Light Emitting Diode and is essentially electricity passing through a chemical mixture that, when energized with an electrical current, emits visible light.
So let’s get the obvious out of the way: Is it a good move to switch? For 90% of applications, it is a resounding yes, do it and do it now. The LED technology has matured to the point that it is stable, it is safe, it delivers outstanding light and is almost as affordable as the old incandescent – and even more affordable than fluorescent. So don’t hesitate – it’s a wise move. Most of all, it is economical.
1) What colour do I choose? It’s a question that was seldom asked in the past, but today, LED replacement light bulbs come in a variety of colour ranges, from a warm, candle-glow yellow to bright blue-white. Colour is referenced by the “Kelvin” or “K” scale, which ranges from about 1000-up. Here’s some references, starting at the lowest available light bulb:
- 2200 K Candle light, yellow-orange
- 2700 K Typical incandescent light bulb
- 3000 K Halogen incandescent light bulb
- 3300 K Many current LED’s are available – a bit more towards the daylight bulbs
- 4100 K Typical laundry-room fluorescent white; cool white
- 5000 K “Daylight”
- 6000 K Blue-white such as in arc-welding and some LED car head lights
The most popular LED light bulbs are in the 2700K to 3300K range. If you want to match the old incandescent, then choose 2700K. If you want to “modernize”, then 3000K or 3300K is good.
HINT: If you are replacing all of the light bulbs in an area, such as in the kitchen pot lights, buy one or two extras as back up. Why, you ask? To maintain consistency should one of the bulbs suffer a failure a year from now. Because the LED world is still emerging and getting better, newer models will replace older models – but in all likelihood, they will not have exactly the same colour output or lumen output. Yes, the store will hand you a new replacement bulb for the old failed one, but in most cases, it is not a new “old” bulb, it is a new, “new” bulb.
2) What wattage? In the past, we were used to the 25 watt, 40 watt, 60 watt, 75 watt and 100 watt incandescent bulbs. But now it’s all different. LED’s use much less power, only about one-tenth of what the old bulbs used.
So a rough guide is 10% of the wattage of the old bulbs, so a 6 watt LED will yield about the same light as a 60 watt incandescent. Roughly, because there is a wide range of LED manufacturers and some are very efficient and effective (90% power savings) and some are less efficient and effective (80% power savings and lower).
The newest generation of LED bulbs, (where the diodes are tiny, but there are many of them), consist of filament strings going from the base of the bulb to the top of the filament holder inside. Each string delivers about one watt of LED output, so a 4-string bulb is about 4 watts or 40 watts equivalent.
Lumens: Light output is measured in Lumens for LED bulbs. Again, here is that guideline of 10… A 60-watt incandescent puts out about 600 lumens of light. A 600-lumen output LED bulb is roughly equivalent to a 60 watt incandescent.
3. Clear of Frosted? This is often misunderstood – most people think that a clear bulb delivers more light, when in application, the frosted bulb delivers more “useful” light. So when do you use clear bulbs with exposed filaments (LED filaments are yellow – bright yellow – so they look much different than the old incandescent bulbs where the filament was almost invisible. The rule of thumb: if your fixture has clear or seeded glass, then use clear light bulbs.
If your fixture has coloured or white glass, then use frosted bulbs.
If your fixture has no glass, just open sockets, then you can use whatever is most pleasing to the eye.
Many newer generation frosted bulbs look identical to the old incandescent types and no longer have the big fat base to them that obstructed the light delivery downward. If you see an LED bulb with about one-third of the bulb as a plastic cone at its base, it is an older generation. Less efficient, more prone to issues.
4. Colour Rendering. The “CRI” – Colour Rendering Index – is the measure of how well a light source activates the complete colour spectrum. Some light sources, such as fluorescent, are notoriously bad for lighting up red-coloured clothes, for instance. Sunlight shows all colours in their natural, pure state.
The CRI runs from zero to 100, with zero meaning no colour at all is seen, and 100 means it is full colour as if seen under natural daylight conditions. Most economical light sources are around 80 CRI; good sources are 90 CRI, Very good sources are 95CRI and the best LED’s you can get hit 99 CRI, but these are very expensive, special-purpose bulbs – not something you will find in the everyday light bulb.
Anytime the CRI is less than 100, some colour in the spectrum is affected more than others. Every light bulb will have a CRI rating, but it will not tell you which colour(s) are affected. That is by trial only. Most lighting stores will have a CRI colour panel so that individual light bulbs can be tested.
In reality, most people do not notice a dulling of colours with a 90 CRI or higher. But at 80 CRI, some colour is definitely dull.
CRI is very important for certain applications, such as lighting artwork. This is where LED’s are NOT a good choice, because there are no LED’s with a 100 CRI. But Halogen light, such as in a focused MR-16 bulb, does, which makes the MR-16 halogen bulb the choice of most art galleries.
5. Dimming. Early versions of LED light bulbs could not be dimmed successfully and in some cases, dimming “non-dimmable” bulbs could cause electrical issues. Whereas all incandescent bulbs can be dimmed, both CFL and LED bulbs must be made specifically for dimming. If the bulb does not specifically say “Dimmable” on its base, it is not.
It goes without saying, that older generations of LED were not dimmable. Also, as a rule of thumb, cheaper LED bulbs are not dimmable – so watch out for bargains, they are usually older generations being dumped on the market to clear stock.
If you wish to dim your LED bulbs, make sure that you use a compatible wall dimmer. These will say on their labeling, LED-CFL compatible. Most newer dimmers are compatible, but older dimmers (three years), especially the old rotary-styles, are not to be trusted with LED’s, and can damage the bulbs, the dimmer, and may even present a fire hazard.
6. Life Span. Most bulb manufacturers represent their LED bulbs to last between 10,000 hours and 50,000 hours. Since most incandescent bulbs are rated between 1,000 and 10,000 hours, it seems like the LED’s win hands down. The “average” incandescent 60 watt bulb lasts 1,000 hours, and then it doesn’t work anymore. The “average” LED 6 watt bulb lasts 15,000 hours, and then it done. Or is it?
Life span in LED means measuring the light output from its “birth” until the lumen output drops to 70% of its initial output. So not dead. In the incandescent, the filament breaks – it is done. In the LED, it is just dimmer. It’s a feature of LED, they just seem to grow tired. The other issue is sudden failure, usually early in its life. Most quality bulb manufacturers, such as Bulbrite, will warranty their bulbs for three years, so just in case it has an “electronic” failure, the source store just hands you a new bulb.
7. Disposal. Because LED bulbs contain electronics, they must be separated from regular household garbage and treated as electronic waste. Most major retailers will have disposal boxes for electronics, including LED bulbs.
Because most LED bulbs are made out of acrylics rather than glass, there is almost no danger from dropping a bulb and having it shatter, like a CFL bulb will. There’s no mercury hazard or other contaminant that would make an LED bulb dangerous if broken open. Just electronics. So much safer around the home with kidlets. PLEASE, dispose of the old CFL bulbs – safely, and NOW – at a proper recycler.
Too much to learn? I agree. Sometimes better isn’t simpler. If you still need a 60-watt frosted incandescent, I just happen to know of a stash…
Rob Van Rycke – Lights ON’s “Technical Specialist” – yup, that old guy upstairs strikes again.
Next month… LED Tape Lighting. Lots of technical stuff concerning what appears to be a simple application.