When researching lighting or shopping for bulbs, consumers will often see three delineations to describe illumination: lumens, watts, and kelvin. It's quite common to be confused about these differences, and because of it to potentially make an uneducated decision. We've already discussed the kelvin color scale and how it relates to outdoor lighting, but here we demystify the terms watts and lumens so consumers can find exactly what they need.
Lumens are a measure of the total amount of visible light from a lamp or light source. The higher the lumen rating, the brighter the lamp will appear; and the lower the lumen rating, the dimmer it will appear. Essentially, looking at lumens lets you buy the amount of light you want.
The brightness, or lumen levels, of the lights on your property may vary widely, so here's a good rule of thumb:
- To replace a 100-watt incandescent bulb, look for a bulb that gives you about 1600 lumens. If you want something dimmer, go for less lumens; if you prefer brighter light, look for more.
- Replace a 75W bulb with an LED bulb that gives you about 1100 lumens
- Replace a 60W bulb with an LED bulb that gives you about 800 lumens
- Replace a 40W bulb with an LED bulb that gives you about 450 lumens
Watts on the other hand, are a measurement of power consumption and energy used. With traditional incandescent bulbs, the higher the wattage, the brighter the light. With energy efficient bulbs such as LED this is somewhat different because there is no hard and fast rule to correlate wattage with output, and LEDs use much less power. One brand's 9 Watt LED bulb may emit enough Lumens to replace a 60 Watt incandescent, but another brand may need to use a less efficient LED such as 12 Watts to create enough lumens to replace that same 60 Watt bulb. Because of this it is much more important to look at lumens than watts when considering light output.