The Difference between Watts & Lumens in Lighting
Lighting has been measured in watts, or energy used to light products, for many years, whereas the lumens indicate the amount of light produced. This difference has made it challenging for the consumer to effectively compare their lighting options. As a result, the FTC mandated in 2012 that lighting manufacturers standardize the language used to describe lighting output. Labels on light bulbs are now required to display the brightness of a light bulb in lumens, rather than simply the amount of energy it uses (watts).
Since lumens have become the standard for lighting they can be used to evaluate the brightness of any light bulb, regardless of the technology. You can accurately compare a halogen incandescent bulb to CFL or LED using lumens. The more lumens the brighter the light. Therefore, lumens give the consumer the ability to more accurately assess their lighting options.
Lumens per watt is a relatively new efficiency measure that compares the amount of lumens a user perceives to the amount of energy (wattage) needed to achieve it.
The chart below shows the brightness levels that can be achieved using different bulb technologies and wattage. As you can see, the LED bulbs require much less wattage than the compact florescent or incandescent bulb. LED bulbs are clearly more energy-efficient and will typically last longer than most other types of bulbs.
LEDs are the leader in lumens per watt and are the future of lighting. LED light bulbs typically use a fraction of the wattage necessary to light incandescent or compact florescent bulbs. LEDs used in your home can save energy, run cooler, and save on the cost of replacement bulbs.