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Constant Light Output (CLO)

“Good for the environment and your finances.”

  • Insights

How Constant Light Output works

Constant light output or CLO for short is a technology that has been available for some time.

A CLO luminaire compensates for light depreciation using a programmable driver incrementally increasing its output current over time to balance LED depreciation.

How can you guarantee a maintained light level in the future when the light source decreases in intensity?

It is an equation that does not go together. The most common solution for lighting manufacturers is to give the luminaires extra power from day one and hope that the lighting requirements are met after, for example, 50,000 hours in an environment. This is called over-illumination, and as a result, the room's light level and energy consumption are unnecessarily high during the majority of the luminaire's lifetime.

This is costly waste, both financially and environmentally. Energy consumption over the useful lifetime of a light fitting accounts for up to 75% of its total carbon emissions.

CLO luminaires with L100 provide a higher maintenance factor, providing a much more optimised system. This is made possible by reducing over-illumination from day one which means less energy consumed and often fewer luminaires to reach the same outcome.

When using CLO, we do not need to compensate for light loss initially; from day one we reduce the flow/power in our CLO luminaires via the programmable electronic system, which automatically and incrementally increases output over the 50,000hrs. This further saves energy and provides constant light output from hour one to hour 50,000.

CLO luminaires with L100 provide more optimised systems, less energy consumption and a lower total cost of ownership.

When we compare three lighting solutions with L70, 80 and 90 ratings against one using CLO L100 it looks like this:

The first three solutions will draw unnecessary power for the majority of their life. In contrast, the solution with CLO will commence output at only where it needs to and incrementally increase to 50,000 hours, perfectly balancing the natural depreciation of the LED.

Both Circadia and ELLE come with CLO as standard. 

You can find a short video of Ian Johnson (Lighting Solutions Manager) discussing CLO and Circadia here:

Read this post by Fagerhult for more detail about CLO.

Contact us if you would like to learn more about CLO and its benefits.