To convert 500 watts to lumens:
Find the type of bulb to determine its luminous efficacy.
Then multiply the wattage of the bulb with its luminous efficacy to obtain lumens.
For example, if our 500 watts bulb has a luminous efficacy of 40 lm/W: The amount of light it can produce will be 500 × 40 = 20,000 lumens.
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