Learn more about these terms.
- Color Temperature
- Beam Angle/Spread
- Wattage
- Lifetime
- Lumens/Watt
- Warranty
Color Temperature
LED light bulbs, like regular bulbs range from Warm White to Soft White to Cool white.
- 4000 – 6500K = Cool White
- 3000 – 4000K = Nuetral White
- 2500 – 3000 = Warm White
Most stores just copy the color temperature from the LED manufacturer they buy from. Often times this is inaccurate. i.e. they’ll say it’s soft white, when it’s actually Cool White, or slightly bluish.
Also they’ll specify a WIDE range, such as 5000 – 7000K. 2000K is quite a big difference in color. Look for side by side comparisons or “real-life” photos of the lights in action to get a good idea.
Beam Angle/Spread
The strength of LED bulbs is directional light – where you need light in one direction. A 60 degree beam is the point where a spotlight starts to become a floodlight. These will be much more focused than the PAR flood lights most people are used to replacing. Between 60-120 is less of a spotlight, while a true flood light is 120 degrees and more.
The measurement for beam angle isn’t standardized so two LED bulbs from different manufacturers with the same beam angle, may actually look quite different. Look for “live-action” side-by-side photos, in addition to the description to make sure the bulb gives light spread that you want.
Wattage
A good rule of thumb, is LED’s use about 1/5 of the energy of their equivalent incandescent flood replacement and 1/2 of their equivalent compact fluorescent (CFL) replacement.
- A 50W incandescent would need to be replaced with a 10W LED bulb
- A 15W CFL bulb would be replaced by a 7W LED bulb.
Many manufacturers exaggerate the amount of light their bulb will give out. To shop smarter, multiply the energy usage of an LED bulb by 5-7 times to get an idea of the incandescent bulb it can replace.
Be cautious of manufacturers claiming their bulbs are any brighter than this, since this more than likely will not be the case – i.e. a 10W LED bulb that replace a 100W incandescent bulb (10 times). As technology improves, LED bulbs will get brighter for less energy, whereby we’lll update this number accordingly.
Item | (6000K) | CFL | Halogen Bulbs |
Life Time | 35,000 hrs | 6,000 hrs | 3,000 hrs |
Typical Power Consumption( =A) | 10.4 W | 23 W | 60 W |
Typical Power Consumption per year (12hrsx365day/KWh)*A=B |
45.55 KW | 100.74 KW | 262.8 KW |
CO2 Quantity (Kgs/year) (0.637*B=D) | 30 Kgs | 65 Kgs | 170 Kgs |
Energy Saving Rate (Compare with CFL) | 55% | ||
Energy Saving Rate (Compare with Halogen Bulbs) | 83% |
Lifetime
The lifetime of an LED bulb does not actually mean it will burn out/die like a regular bulb (if it’s properly made). LED light bulbs are unlike incandescent bulbs in that they lose their brightness over time and by the end of their rated “lifetime”, they are at 70% of the brightness they started at as opposed to completely burning out.
Many sellers copy the lifetime ratings of the manufacturers, which are OFTEN inaccurate, or just false. Many claim their bulbs last 100,000 hours. We’ve spoken to a number of LED manufacturers from around the world and many of them are now more conservative about their ratings – saying they now last 35,000 to 50,000 hours. Your best bet is to buy from a seller with a good warranty, and expect to get what you pay for.
Lumens/watt
This is a simple way to measure the efficiency of a bulb. Lumens is a measurement of the total amount of light given out. A high lumens/watt means you are getting more light for less energy.
- Incandescent bulbs are typically 20 lumens/watt.
- CFL bulbs range from 60-70 lumens/watt.
LED bulbs can range from 40-80 lumens/watt.
However if the seller has inaccurate lumen ratings, then this calculation will come out wrong. Your best bet is to SEE side by side comparisons to a bulb that the LED light bulb will replace. Here’s a good article: why lumens is a bad way to compare led light bulbs to CFL bulbs.
Warranty
Look for at least a 2 year warranty on LED bulbs. A 3 year warranty is even better and shows the seller truly stands by their product. Settling for anything less is asking for trouble.
A bulb run for 24 hours a day for a year is about 9000 hours. 2 years is 18000 hours – do the math – if a seller says a bulb will last 50,000 hours, but only warranty it for 1/5 of it’s life, it doesn’t say much about their confidence in their products.