What Are Lumens?

An easy switch to more energy efficient lighting starts with swapping CFL’s for old incandescents.

What are Lumens?

“What are Lumens?” is a question that may only be answered by physicists and light bulb makers – it certainly leads to more complicated questions! At the risk of delving deep into science however, here is a simple explanation will help clarify.

Lumens are a form of light measurement in brightness. To put it simply, one lumen is the amount of visible light that is given off by a light source. One lumen is equal to the glow of one candle, at its source. Putting it that way seems really simple, but still it becomes more difficult when you realize that before now, all light bulbs’ efficiency was measured in watts.

Are lumens the same as watts?

Old school light bulb shoppers would recognize that older incandescent bulbs are measured in watts. What’s the difference? A light bulb’s wattage is how much energy is consumed by the bulb while it’s on. Lumens have nothing to do with that, because while a light bulb may be 100 watts, it may only put out 1000 or 1100 lumens – depending on age and type.

800 lumens = 800 candles = 60 watt INC bulb.

Example: A 13 watt energy efficient flood lamp might only use 13 watts of energy, but this isn’t an ordinary incandescent bulb. This compact fluorescent light puts out about 800 lumens, which for an incandescent is the equivalent of a 60 watt bulb. That is a lot less energy for the same amount of light.

Other kinds of light bulbs produce even more lumens than compact fluorescent.

Of course other kinds of light bulbs do an even more spectacular job at lighting your world. For instance, a high intensity discharge post light at 70 watts produces about 6300 lumens. That’s enough to light the entire street, a full 300 watts. A Mini HID flood light can be found in 35 watts, but still puts out about 2250 lumens of light.  That is a big difference from traditional tungsten incandescent light bulbs, for which 35 watts would hardly light a small room.

Light temperature has a definitive affect on lumens as well.

Light temperature is also a factor on the level of lumens that a light bulb produces. The temperature of light is measured on the Kelvin scale. The lower end of the spectrum provides the soft yellows and the higher end of the scale provides extreme white or blue lights.

Light measurement is simple once you learn the technological lingo. “What are lumens?” becomes an approachable question and the choice of your lights bulbs becomes easier when you are looking for energy efficient lighting for your business or home.