The light at the end of the tunnel

By Joseph M. “Jody” Good, III, LC, FIES, IALD, LEED AP, Spectrum Engineers, December 16, 2009
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    For many of us who design lighting and lighting control systems, the recession may have severely curtailed our efforts to continue designing state-of-the-art systems. The recession also may have thwarted our ability to stay abreast of changing user attitudes and technological innovations in real-world applications. As a result, many of us may have missed out on designing the lighting and lighting controls projects that people will likely want when construction begins to rebound in earnest.

    LED lighting and lighting controls

    If you, as a lighting designer, suddenly fell asleep two years ago and just woke up today, what changes would you notice? You would find that two areas of the lighting industry have continued to develop during the recession: LED lighting and lighting controls. This is due, in part, to the federal government passing legislation, underwriting research, and funding construction that encourages the adoption of these technologies. The most recent legislation continues to encourage the use of more energy-efficient solutions and reward exemplary projects. The market buzz associated with LEED certification played a large role in promoting interest in these technologies.

    The surge of interest in sustainability means that, for lighting designers, energy conservation has gone from selecting the latest energy-efficient ballast and lamp to genuine integration into the design of the project. For example, going from standard-ballast factor to low-ballast factor saves about 15% in energy consumption. There are even lower ballast factors that can save an additional 10% or more. However, changing a building’s architecture to maximize daylight and accommodate new luminaires and lighting solutions would increase savings even further and provide occupant comfort.

    The use of lower-wattage luminaires, closer integration of lighting and architecture, and the implementation of sophisticated control systems all combine to help the mechanical engineer design cooling systems to lower energy loads. The lower energy loads will provide opportunities for energy savings.

    Energy efficient lighting sources

    The industry is also putting great focus on efficient light sources, especially LEDs. Today, offices are being designed at less than half the W/sq ft Lighting Power Density (LPD) than a few years ago. This requires intense coordination between the architect and owner, and more consideration from the lighting designer than simply thinking in terms of LED downlights.

    Two such office projects come to mind as particularly successful; both used daylight whenever possible and both required the management of daylight and the education of users about daylighting benefits. In the expansion of an architect’s office, the architect allowed significant use of daylight, which increased occupant comfort through lighting, daylighting, and outside views. The LPD was approximately 0.66 W/sq ft. In a recent office tenant improvement project, which used LED technology extensively, the LPD was 0.47 W/sq ft (per ASHRAE/IES 90.1 )—approximately 57% under allowed LPD. The design of the office tenant project helped save approximately $400/month in lighting electrical costs, plus savings from occupancy sensors.

    In both cases, the lighting designer was responsible for luminaire selection and lighting control design, while the owner benefited from lighting design, daylighting, and reduced cooling loads. Close coordination with the architecture maximized employee exposure to daylight and views, and provided control for the daylighting. Individual occupants were provided with the necessary individual controls, which promoted their own personal comfort.

    When designers think in the 3-D, full-visual, environment sense and get clients and employees to buy in as full stakeholders, then ambient levels can be reduced significantly. A comfortable balance between ambient and workstation lighting must be sought, and lighting for paper-based tasks must be treated in a localized, on-demand manner.

    Applications, benefits, and future of LED lighting

    The economies of LED lighting are certainly working in the buyers’ favor because the promised technical capabilities are being realized. Color is being improved almost on a monthly basis. Improvements in anticipated electrical efficiency (the usable light per watt) are coming more slowly, but they are coming.

    There is still great resistance in certain market sectors, like hospitality, to most efficient lighting solutions. Starting in 1999, government influence has become necessary to move the market away from the least-efficient lighting sources. Even in the last two years, lighting sources that do not involve LEDs have benefitted from new products and efficiency improvements.

    Advances in control technologies have made them more capable, easier to specify, easier to install, and much more user friendly (e.g., the advent of wireless occupancy sensors, self-contained daylight harvesting controls, and intuitive network-based platforms for larger, more integrated control systems).

    Municipalities are adopting ordinances that restrict light trespass, eliminate sky glow, and observe curfews to preserve the night. Associations such as the Illuminating Engineering Society of North America and the International Dark-Sky Assn . have helped implement these changes and have now agreed to the Model Lighting Ordinance. These ordinances are appearing in many locales and are adaptable to existing and new lighting technologies.

    Call to action

    The time is now to prepare for the day when each of us is designing lighting projects that challenge our abilities and push us toward innovative solutions for integrated, intuitively controlled, and energy-efficient lighting systems. We may be seeing the first glimmers of light at the end of the tunnel. If this is so, we can expect more demanding projects, some with larger budgets, and all with codes and goals associated with some form of improved energy efficiency.

    To be ready, we must:

    1. Review current energy codes. They are continuously changing. Pay attention to the latest LPD and control requirements.

    2. Help our clients understand that we cannot light an office to 100 ft candles anymore.

    3. Coordinate with the architect and interior designer to fully integrate lighting into the architecture so that the best lighting solutions no longer look like an addition to the architectural design, but an integral part of it. Given the amount of retrofits and renovations occurring as owners seek to make buildings last longer, be careful to match lighting designs with existing conditions, especially with historical precedence.

    4. Make a real effort to stay current on light sources. As with any developing technology, we must remind ourselves not to believe everything we are told.

    5. Keep learning. It is generally acknowledged that LEDs make sense in many downlights, some recessed rectangular luminaires, and some outdoor luminaires. Education remains the key to determining what is really practical, what is promising, and what is misguided in these applications.

    6. Never incorporate control systems that are more complicated than the owner and occupants are comfortable using.

    7. Be the gatekeepers and distinguish whether fads are fact or fiction.

    No matter how experienced lighting designers think they are in the design of the most modern lighting and lighting controls systems in real-life applications, a little review and critical thinking about lessons learned in past projects is always helpful. Even designers who have been involved in high-profile, state-of-the-art lighting projects during the recent recession would benefit from taking a look at items one through seven.

    The more knowledge and experience each of us incorporate into our work, the more our industry will be able to design the types of systems clients and users want and need. It will be easier for us to fulfill our obligation to educate them about the significant advantages that new technologies, true integration, real collaboration, and sound design can offer them.

    Author Information
    Good received his B.F.A. in theatre and lighting design from the University of North Carolina. He is a principal at Spectrum Engineers. He holds the Lighting Certified designation from the National Council on Qualifications for the Lighting Professions. He is a professional member of the Int’l. Assn. of Lighting Designers and the U.S. Institute of Theatre Technology.