Watt vs Lumens: How bright is that light?
With the introduction of CFLs and LEDs, the way light bulbs are rated has evolved along with the bulbs.
Relying on the traditional Watt, which is a measurement of energy, can make it difficult to compare incandescent bulbs to the more energy efficient bulbs, such 
as CFLs and LEDs, which can use up to 80% less energy, or watts. But now there is now a standardized measurement for the total emission of light or brightness, and it is called Lumens.
According to the U.S Department of Energy, upgrading 15 inefficient incandescent light bulbs to CFL or LED bulbs could save about $50 per year. Ninety percent of the energy used by a traditional incandescent bulb is given off as heat. That is a lot of wasted energy!
The Federal Trade Commission (FTC) and lighting manufacturers are placing more information on light bulb packaging to make purchasing easier. The new light bulb labels include brightness measured in lumens, the estimated yearly energy cost in dollars, the life expectancy of the bulb, the light appearance from warm to cool and the energy used measured in watts. This information can help consumers make a more-informed decision when it comes to purchasing light bulbs.
These new labels will help consumers make purchasing decisions as they transition to more energy-efficient types of bulbs.
Sources:
Alliance to Save Energy, Energy-Efficient Lighting: Lumens vs. Watts
National Geographic, Green Living, Lumens vs. Watts for LED Bulbs