Save Energy! How to Calculate Lumens Per Watt May 21, 2010Posted by bowmanlamps in compact fluorescent.
When shopping for light bulbs, it makes more economic and environmental sense to purchase the ones that produce more light with less energy. Lumens Per Watt (LPW) is used to show how much light is produced for each watt of energy used. It’s as easy as 1, 2, 3 to determine the LPW for each light bulb, or lamp as they are known in the lighting industry, to make sure you are getting the best deal.
- Find the lumen output number on the light bulb box. This indicates how much light the lamp produces.
- Watts indicate how much energy a lamp uses. That number is printed on the box and the bulb.
- Divide the lumen output number by the light bulb wattage to get the LPW. It’s that simple.
Keep in mind compact fluorescent lamps last longer than standard incandescent light bulbs, but their light output decreases over the life of the bulb. Light bulb manufacturers provide both an initial lumen rating and a mean (average) lumen rating. Whether you are buying one light bulb or outfitting an office, purchase lamps with the highest rating to get the biggest bang for your buck. You’ll get the most light for the least amount of electricity. And while you may not notice much of a difference if you are purchasing one light bulb, imagine the energy savings for a hotel or store.