The Controls Layer

JAMES R. BENYA, PE, FIES, FIALD

Even in the most basic of lighting situations, providing manual control of lighting is fundamental. Giving choice to the user permits a light source or scene to be energized.

In my June 2023 column, I revisited my personal design theory of lighting by layers, which I believe is a good fundamental technique that can be taught and eventually becomes innate with experience. But, as I noted, my layers were unveiled in the late 1990s when major changes in lighting controls were underway, and more importantly, long before LED lighting was efficient enough and practical for general lighting. Lighting controls had advanced considerably since the first generation of what we now call lighting designers began to employ lighting controls as a design tool. Yet, compared to today, little was possible, and the user interface was limited. My, we have come a long way.

For indoor architectural lighting purposes, it’s probably best to differentiate among the over-arching “controls strategies” that lighting controls might employ in a particular space or building. These strategies are not standardized – heck, this article caused me to come up with them, and others might not agree. But I think that these fit the majority of approaches to controls.

Energy Codes and Efficiency

This strategy is a slave to energy efficiency codes and standards like California Title 24 and ANSI/ASHRAE/IES 90.1 that have specific requirements including automatic shut-off (motion or time based), dimming controls, and daylight harvesting. Manual controls and manual overrides are permitted in some cases. Compliance is mandatory for government projects and in states that have adopted it. But we can get carried away with automation. For example, in Title 24 proceedings, I argued against certain automatic switching in homes and hospitality environments that could cause safety or security problems and successfully limited the locations where Title 24 requires motion sensors.

Convenience, Hospitality and Identity

Even in the most basic of lighting situations, providing manual control of lighting is fundamental. Giving choice to the user permits a light source or scene to be energized. This strategy employs manual control stations and is particularly important in residential and hospitality spaces where automatically switched lights would be a distraction and detract from the quality of the environment, day or night. For example, the lighting for a hotel lobby should be inviting and speak to the character of the property, even at 3 a.m., and hotel room switching should be left to the occupant.

Functional and Occupant-Selected Scenes

Lighting scenes are an important part in the artistry and/or functionality of the lighting in many space types. Until energy codes mandated controls, scene controls were, from my experience, the primary reason to have more than dimmers and switches, as they enabled a lighting design intent to be realized with the push of a button. I still use this approach, except codes will now require an automatic “off” function, usually using a time function to ensure lights are turned off during periods when the facility is closed. I think the most difficult spaces to design are performance venues where both theatrical controls and architectural controls have to (hopefully) work in unison.

Wellness

As we learn more about the role of light in what we now know as “wellness,” there is an increasing demand for lighting that provides positive reinforcement to circadian systems. Wellness controls may be highly integrated with daylight and shading controls to ensure proper directionality, intensity, duration, timing and spectral control of light exposure to occupants of a space. As I see it, the broad concept of wellness can also be applied to lighting in indoor agriculture, animal husbandry and zoos, medical facilities, and other indoor environments, and it is not just limited to human work and living environments.

Common Sense

When all else fails, electric lighting is an integral part of living for most people. As the efficiency of LEDs has increased, the waste of electrical energy has fallen dramatically. But energy should only be part of the reason for lighting controls of the right type and reason for the situation. That’s my job and yours.

I have generally not included theaters and similar spaces where there is a clear link between management and lighting operations, but even that is changing with the house lighting control being tied to an automated projection system. My primary concern with automated environments is what happens when things go wrong. Having an effective and accessible override is essential in any public building for emergencies, and of course it should be designed to provide emergency lighting in power outages. In this capacity, the more manual, usually the better.

Pre-set scenes date to the use of theatrical lighting systems and then, after dimmers and motion sensors, were among the first lighting controls to gain wide acceptance in every application from residential living rooms to hotel function spaces and board rooms. What I particularly appreciate about scene dimming is that is preserves my design intent for the layers of lighting in the room it controls. In some rooms, it is essential for creating the right ambience or mood, as in a restaurant; in others, the scenes are coordinated to accommodate video environments that can change to become paper-intensive work or meeting environments, or perhaps to support the action in a concert or nightclub facility. Gone are the days of projected video and its low luminance needing a dark room, but lighting controls are still a tool for changing the luminance balance of a meeting space for recording or dramatic effect. All of this is good, as it expands the role of the lighting designer to more closely resemble that of the lighting designer in the theater. You create scenes and moods that can change with occupancy, time of day, daylight, and other factors like media. So, as you might imagine, the latest innovations in lighting controls expand and, for many projects, spread, the same challenges.

There is of course, one big movement gaining strength that involves lighting controls. In today’s market, there is an over-arching temptation to integrate building energy systems with lighting control systems. In an email blog I got the other day, our Editor, Randy Reid, presented his take on “Unlocking the Potential of Networked Lighting Controls: Insights from the DLC Controls Summit 2023.” Today, David Shiller wrote in LightNOW, “Here Comes the Lighting-HVAC Integration Tsunami.” The idea is to employ the lighting control system to provide additional information to the HVAC system, and with the added connectivity, HVAC systems can operate more efficiently.

This idea is not new. I call your attention to my February 2023 column, “What Could Possibly Go Wrong,” in which I describe a new-in-2015 energy management system for a school that could not turn the lights off – ever. The system itself had failed, and because it was so highly integrated with all building systems, became a massive liability because the manufacturer was bankrupt and gone. To prevent this, I tend to specify systems from reliable, established and yet progressive companies, so I can sleep at night…

Personally, I am torn. The integration of lighting controls and HVAC controls has been a dream since the first programmable energy management systems of the 1970s, but the truth is, the electrical industry speaks a different dialect from the HVAC industry. David Shiller makes the point that LED “socket saturation” has reduced lighting power density in commercial buildings so much that sophisticated penny-pinching controls are hardly warranted. But extending their role to better manage HVAC systems is worth looking into – and perhaps, may serve as the foundation for completely integrated building controls including the management of solar energy systems, battery storage, vehicle charging, and other energy uses. I think the lighting industry, our government agencies, and our industry organizations have done a superb job of reducing the energy consumption and carbon footprint of lighting with LEDs and control systems that are robust and reliable, but the integration with other energy uses in a manageable building is still evolving. I hope David’s “tsunami” is a friendly one that resolves the many problems and challenges of lighting and HVAC living and working together in ever more efficient and pleasant buildings of all types.

Finally, the layer system breaks down outdoors, and new issues and meanings are needed. I’ll save that for future thoughts on outdoor lighting. As one might guess from my years of service with the Board of the International Dark Sky Association, I will try to explain how a host of environmental concerns and protecting the night sky are on track to collide with increasingly capable outdoor lighting and special effects, and how design professionals might address the challenges.