A lumen is a unit measurement of light. To determine the needed lumens, you will need to multiply your room square footage by your room foot-candle requirement.

What about lumens versus e-lumens, another figure you may see included? The difference there is that the e-lumen number refers to light output after it's been in use for, say, 30 minutes.

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Creed Monarch, a contract manufacturing facility in New Britain, CT, has recently deployed the Digital Lumens Intelligent Lighting System, and is achieving 75% energy savings. Creed Monarch ...

One company benefiting from that perception is LED lighting company Digital Lumens, which just scored a $23 million Series C funding round.