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Lighting For LEED

By Mark Loeffler, IALD, LC, LEED

The LEED (Leadership in Energy and Environmental Design) rating program has emerged as a very influential driver for U.S. facility design and construction. Sustainable lighting design strategies and specifications can play an important supporting role for projects seeking LEED certification.

The IALD (International Association of Lighting Designers) Sustainability Committee defines sustainable lighting design as meeting the qualitative needs of the visual environment with the least impact on the physical environment. Visually effective and appealing, high quality lighting provides the greatest environmental and economic value. The hallmarks of sustainable lighting design also include:

• Optimizing the use of daylight ing;
• Minimizing the use of energy;
• Avoiding skyward illumination; and
• Encouraging environmentally responsible manufacturing processes and materials.

LEED version 2.1 for new construction, as well as upcoming programs for existing buildings and commercial interiors are of particular interest to facility managers. These programs help create more efficient and healthful facilities and can be part of an organization's environmental management system.

Lighting contributes directly or indirectly to many LEED credits in the green building categories of sustainable site work, energy efficiency, alternative materials, and indoor environmental quality. Therefore, a sustainable lighting design approach is key in a LEED project.

Sustainable Site Lighting

LEED offers a credit for preventing light pollution-light that indiscriminately goes upward obscuring the stars and wasting energy. Environmentally preferable outdoor lighting prevents glare from shining into the sky or onto others' property. New work by the Illuminating Engineering Society and the International Dark Sky Association indicates that moderate levels of glare free, high color rendering, white light are best for nighttime vision and security. White metal halide lamps are preferred to yellowish high pressure sodium lamps. Well shielded "cutoff" luminaries are favored, rather than floodlights and wall packs that shine light above horizontally.

Energy Effective Lighting

Energy savings offer the most credits of any LEED category. Since lighting accounts for about 40% of the energy use of a typical commercial facility, energy effective lighting can contribute directly toward LEED certification.

Facility managers are well versed in the energy benefits of high efficiency fluorescent and compact fluorescent lamps, electronic ballasts, and occupancy sensors. A lighting design strategy that also integrates daylighting to minimize the dependence on electric lighting can produce tremendous savings over typically uniform lighting layouts.

New technologies, such as T5 and T5HO fluorescent lights, high-color rendering ceramic metal halides, dimming ballasts, and daylight dimming systems can provide even more savings. And, lighting energy reductions translate into air conditioning savings, as well.

Lighting Material Alternatives

LEED provides numerous credits for using alternative materials that are salvaged, recycled, renewable, or available locally. Mechanical systems and lighting equipment are not typically included in these considerations, but planners can support LEED goals with careful specifications.

This might mean refurbishing and reusing existing luminaries or selecting equipment manufactured within 500 miles of the job to save transport energy. A little research will reveal manufacturers that promote environmentalism using recycled/recyclable packaging or less toxic production methods. Lighting specifications can stipulate features such as lead free components and powder paint finishes to encourage manufacturers to improve continually the environmental characteristics of lighting products.

Daylighting

Under the category of indoor environmental quality, LEED provides credits for daylighting and views. Good daylighting is a result of careful architectural design to optimize lighting but shield glare and maintain thermal control. High performance insulated windows, effective shading and window treatments, daylight oriented interior designs, and reflective finishes can add up to well lighted facilities that need minimal electric lighting during the day. Neutral tinted, low emissivity (low-e) windows provide both natural colored lighting transmission and solar heat rejection. Combined with the bonus of views to the outside, daylighting helps create more desirable and productive facilities.

Extra LEED credits are awarded for particularly innovative design strategies. Techniques that improve lighting quality in addition to providing environmental benefits are encouraged and may be rewarded. An added credit is given for having a LEED professional on the design team, which is an accreditation that some lighting designers bring along with a sustainable approach to lighting design.

When it comes to lighting, energy saving techniques and environmentally sound lighting alternatives can go a long way to save the budget and be a friendly, green measure for the company.