I recently stopped by the hardware store to buy a few light bulbs and found myself standing in the shoes of the typical consumer – making my decision based on the information available on the box. Watts. Necessary? Yes. Sufficient? No.
Sure, watts matter. But there is much more to the story, especially as new lighting technologies like LEDs come to market. A 9W LED lamp will produce the same amount of raw light output as a 60W incandescent. Labeling for wattage alone is analogous to food labels when they only listed calories. No breakdown of fat, carbohydrates, protein or other nutrients. That is where we are in the lighting world.
With food labels, people look for the information that is most meaningful to their interests. Endurance athletes may be checking for a protein-to-carbohydrate ratio, while a diabetic will be checking for grams of sugar and still another person may be trying to reduce fats in their diet. You get the idea. For lighting, the same principal applies. The information that is most meaningful depends on your particular situation and concerns. Are you lighting an office, parking garage, manufacturing space? What are people doing in that space? What are the expected and necessary light levels and light qualities?
As LED-based lighting solutions move from brake lights and traffic signals to being used as an illumination source for a variety of situations, we need to think carefully about how we label and decode the information that prospective customers get. The lumens-per-watt ratios continue to improve rapidly, but that information doesn’t necessarily tell someone whether a given light is suitable for a given application. Are those lumens going where you need them to go? Are you turning the light off (or dimming) when it is not needed?
The industry is making strides as it moves from esoteric, laboratory environment tests that strive to provide a basic level of assurance to customers. But we still have a long way to go to provide an in-the-field understanding of systems’ performance. Labeling that accurately represents a light’s performance metrics for a specific application is what the industry – manufacturers, specifiers, and utilities – need to deliver if we want to ensure that customers get the performance that they are looking for.
When a customer is considering lights, they want to know how much light will be delivered and how much energy (kWh) will be used. This requires a customer- and project-centric approach rather than a lamp- or fixture-based approach. Translation: will the light be sufficient and energy-efficient for my application? My view is that we need to give customers as much information as possible – the nutrition label on the back of my granola bar has 40 numbers I could use to make my decision.
We will definitely come back to this topic in the not-too-distant future, diving in from a deeper technical perspective. In the meantime, if you have thoughts on this issue, please share them via comments.