What Is Luminaire Efficiency, and Why Should I Care?

There is a greater focus on energy efficiency in the home than there ever has been before, and that extends to lighting. Luminaire efficiency is just one term that’s become a part of planning out more energy-efficient home features, and thus it’s a term you should be familiar with as a homeowner working with professional lighting designers in Raleigh, NC to decrease your energy bills. Here’s an overview of what you should know.

The concept of luminaire efficiency

Luminaire efficiency refers to the ratio of light output emitted by the luminaire (the complete light fixture) to the light output emitted by its individual lamps. This essentially means it’s the percentage of the light produced by lamps that are emitted by the luminaire.

Luminaires and their efficiency are evaluated based on the center beam candlepower (candela), efficacy rating (lumens/W), total input watts (W), efficiency (the fraction of lamp lumens that exit the luminaire), coefficient of utilization (CU) and comparative yearly energy cost of light as a function of dollars per thousand lumens.

It’s important to note that not all light produced by lamps exits the luminaire, as some stays trapped inside and gets dissipated as heat rather than light. The physical characteristics of the luminaire determine the amount of light that will exit it and how much will specifically be directed at the workplane.

Why is this concept important?

The concept of luminaire efficiency is important because if you do not have a luminaire that’s efficient at delivering light, then the lighting system as a whole will not be able to be considered efficient. Some of the factors that will affect luminaire efficiency include the shape of the luminaire, how reflective its materials are, the number of lamps inside the luminaire, the proximity of those lamps to each other and whether any shielding material is used to scatter or otherwise soften the light.

It’s in your best interest to seek luminaires with a high level of efficiency. However, there does come a point where the importance of luminaire efficiency can actually be overvalued. Consider this: a completely bare lamp will result in 100 percent efficiency, but it will not provide much in the way of aesthetic value. To bring a lamp into your home that complements the aesthetics of your interior design, you’ll have to compromise slightly on luminaire efficiency, as you’re almost certainly not going to have a 100 percent efficient lamp.

The most efficient luminaires are actually likely to provide some glare as well, which isn’t ideal for certain circumstances. This is especially a problem with unshielded luminaires that have direct distribution at lower mounting heights.

Are you interested in learning more about the concept of luminaire efficiency and why it’s important for you to consider as part of your efforts to reduce your energy consumption? We encourage you to contact Box Electric Company in Raleigh, NC today with any questions. Our professional lighting designers would be more than happy to speak with you on the subject in greater detail.