Michael Lane LC

archived articles

Quality Lighting
October 1997

In May I said, "The focus of most utility programs has always been just three things: SAVE ENERGY, SAVE ENERGY, and SAVE ENERGY". For that statemant I have taken some heat for that statement from my coworkers and from some of you. I still believe that statement to be basically true. The big question is, how can the desire for energy efficiency be balanced with the need for quality lighting?

Maybe what we really need is a new term: "Quality Energy Efficient Lighting" or "Energy Efficient Quality Lighting." Well, that sounds good, but what does it mean? The first thing to do is define Quality Energy Efficient Lighting, which is going to be hard. Energy Efficient Lighting can be defined as using the highest lumen per watt light source, and most efficient luminaire for the task.

Quality lighting which is often seen as the opposite extreme, is much more difficult to define. Quality lighting could be defined as using the best light source and the best performing / most aesthetically pleasing luminaire for the task, with a dash of pizzazz thrown in for good measure. Unfortunately, that is a simple definition for a very complex idea, and I 'm guessing that all of you would define quality lighting differently. And I just fell into the same old trap: trying to separate energy efficiency and quality lighting.

Quality lighting should be a combination of these two concepts: using the most efficient light source in a luminaire that integrates with the architectural design to create a eye pleasing scene. Note that I did not say, the most energy efficient light source, I said the most efficient light source. There is a big difference.

As an example lets look at 90 watt PAR38's versus a 20 watt screw-in CFL reflector for display lighting. According to the IESNA, we should provide three times the light on the displays as for the circulation, and 15 times the light on featured displays as for the circulation. The flood version of the 90PAR/H/FL has a center beam candlepower of 4500 versus, maybe, 800 for a typical 20 watt CFL. To produce the same punch on the display, six CFL's would be needed to match the Halogen PAR. That's 120 watts for the CFL compared to 90 watts for the Halogen to produce the same punch on the display. Yes the beam spread of the CFL is larger and will cover more area than the Halogen flood. But if covering a large area is what you are trying to achieve, then rely on the general lighting not the display lighting. This is why I feel that the 20 watt CFL is totally inappropriate for display lighting because of its lack of punch, but unfortunately I have seen it used to often.

If we go back to my definition of quality lighting (e.g., using the most efficient light source), from a true efficiency standpoint the 90PAR/H is more efficient than the 20 watt CFL: Fewer lamps, fewer luminaires, fewer watts, fewer dollars to produce the desired lighting effect. Now I bet that there are some very upset people out there already writing a letter to the editor because you disagree with me. You think that the CFL is a great light source and I'm degrading it; it is a great light source, but not in this example. It's great for lighting up large areas -- such as for wall washing and down lighting -- but not for display lighting. Then there are the others out there who think that MR16's or maybe the new Ceramic Metal Halide PAR is better. Maybe they are in certain situations but not in all, just like the 90PAR/H is not the right lamp for all situations.

Back to the definition and the second part: "...in a luminaire that integrates with the architectural design". I know what I like in the look and performance of the luminaire: a clean and simple design. This is the look and every designer has there own look.

Quality construction of the luminaire that will provide the owner years of trouble free operation. I'm sure we can all agree with the quality construction part; but wait, then why are there so many CHEAP lighting products on the market? It's because the owner often will not pay for a quality lighting product.

A rep told me about a bollard installation in which he recommended that the owner buy a $400 bollard versus the $250 dollar bollard that was specified. Since the rep handled both lines it didnt rally matter which one the owner bought. And as the rep said "I'll make more money off of the $250 bollard than the $400 bollard, because the $400 dollar bollard can take much more abuse than the $250 bollard". Sure enough the owner was back the next year looking for replacements. Quality lighting is not just how the project looks the day the installation is done or when the IIDA photographs are taken; it's 5, 10 or 20 years down the road.

The last part of the definition is "to create a eye pleasing scene". Again this is a look which many designers work hard at creating. I'm not against fun or dramatic lighting that produces a WOW lighting design. However, I have found that most lay people (customers and end users) will not notice a good quality lighting design when they walk into a room. They will have a good impression about the space though, and yes they will notice the WOW design. When they enter a space with a poor lighting quality, they will sense that something is not quite right, but will often not be able to say it is the lighting.

A space that is too hot because the HVAC is not working properly is immediately noticeable, but a space with lamps hanging out of the luminaires, burned out lamps, color shifting Metal Halide lamps, mismatched lamps, and wall washers facing the wrong direction are not as obvious.

Quality lighting "using the most efficient light source in a luminaire that integrates with the architectural design to create a eye pleasing scene" is important because it's our livelihood. Energy efficiency is only one part of that equation, but it is part of quality lighting.