It's not a strictly linear relationship (like km and mile, or USD and GBP, or Celsius and Fahrenheit), as you can see in the tables google found for me: 40 W + 60 W = 100 W, but the lumens don't add.
http://eartheasy.com/live_led_bulbs_comparison.html
http://lumennow.org/lumens-vs-watts/
Kees
How would I get a comparison chart between the LED, CFC and the old wattage type bulb? I enjoyed the article but still confused about Lumens and Watts.
john

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