Material Considerations

These days, there is an increasing emphasis on making everything we do sustainable. Competition in the marketplace has taken us well beyond LEED, and in order to be “greener” than one's rivals, it helps to be able to embrace as many life cycle and environmental issues as one can. Architect William McDonough and chemist Michael Braungart's “cradle-to-cradle” philosophy, which advocates a “reduce, reuse, recycle” approach to the environment and our consumption of materials, is a starting point for how involved in this we, as both designers and citizens of the planet, have to be.

When it comes to lighting, it's important to remember that first and foremost, the greatest impact to the environment is energy consumption. Unless the energy source is totally sustainable, such as wind or solar, the greenhouse gases and air pollution resulting from electrical energy generation are by far the most significant impact caused by electric lighting. Moreover, even with sustainable sources of power, using light needlessly or inefficiently is depriving the nation's electrical grid of valuable watts that could be used for more-pressing demands. Conservation through the use of daylighting, lighting controls, and efficient sources still remains lighting's principal sustainability consideration.

The next largest consideration is mercury. High efficacy light sources including fluorescent and metal halide rely upon it. And while significant reductions in mercury have occurred in mainstream T8 and T5 lighting systems, the mercury content in compact fluorescent lamps and metal halide remains a lot higher. Recycling of spent lamps is essential. However, until there is a more efficacious choice, remember that the mercury emissions of coal burning power plants, which place mercury throughout the environment, are a bigger threat, so don't start a “Ban the Bulb” campaign just yet. Instead, emphasize low-mercury T5 and T8 lamps in as much of your design as possible. And, of course, make sure mercury is not part of any control system or component.

Once these issues are resolved, it's time to focus on the details of the lighting system. There are a number of things you can do to make your design even greener, as follows.

When evaluating the sustainability of a luminaire, it helps to address every material, with specific attention to the following key issues:

To assess these issues well, it will take a lot of homework. As an example, gold is used to make critical connectors for, among other things, lighting and control systems. When mined, gold is often amalgamated with mercury to form solid nuggets. For every gram of gold obtained using this technique, 1 to 3 grams of mercury are washed into the watershed, in turn becoming the neurotoxin methyl mercury and accumulating in the flesh of carnivorous fish. As with many resources, this illegal process remains widely practiced because it is more profitable than more environmentally responsible methods.

Almost every luminaire uses a metal housing. The most common material is steel, and because lighting is seldom structural, using thin gauge and/or recycled material is a good start. The side effects of iron mining and processing are substantial. Aluminum is another popular choice, but in addition to the impacts of mining, aluminum has an extremely high-embedded electrical energy use. Recycled aluminum is available and represents a moderately responsible choice. But for all forms of metal processing, about 12 percent of the cost is for oil-based solvents and chemicals. You might consider wood luminaires, but be sure to employ rapidly renewable wood and non-volatile organic compound (VOC) finishes. Perhaps the best advice is to use smaller, lighter weight fixtures—the less material, the better.

The luminaire's reflective surfaces are often metal-backed as well. Today's highly reflective (95%+) polished and finished aluminum and extremely white paints are essential in making efficient luminaires. Anodizing aluminum uses considerable electrical power, while powder-coat painting, an otherwise environmentally friendly process, uses petroleum byproducts and electrical energy. Water based paints probably won't hold up well enough for this application, but traditional high-VOC paints and finishes should be avoided unless environmentally contained and rendered benign.

Next up is refracting media. Plastics are widely employed in lighting, but the fossil fuel base, shipping issues, embedded energy, and environmental shortcomings are significant. Consider glass: It has high embedded energy, but it is generally environmentally benign (even with high lead content), and when the product life ends, glass can be recycled and used to make other products. The trade-off is that plastics, while posing an environmental issue from “cradle-to-grave,” offer superior resistance to breaking and shattering. Plastics used in lighting seldom end up recycled.

Then there are the electrical components. Because UL and other regulations are so specific, it will be difficult to choose internal components from a sustainable standpoint. Still, where you have choices, make them carefully. For instance, use the “efficient” ballasts for T8 lamps—they save at least 10 percent of the energy of the T8 system.

Perhaps the best way to ensure the most sustainable lighting is to ensure that the manufacturer's practices are sustainable. Domestic and European lighting manufacturers are required to meet comparatively rigid environmental restrictions. Many have taken additional steps to follow ISO 14000/14001—a series of international environmental management systems—and other standards including environmental auditing, environmental performance evaluation, environmental labeling, and life-cycle assessment. As a minimum, these mean the use of environmentally favorable materials, design and manufacturing processes, packaging and transportation methods, installation and maintenance procedures, and disposal and recycling programs. Products from Asian manufacturers, including major components and subassemblies, should be carefully checked to determine whether the factories and business practices meet these and other U.S. or European Union standards.

Finally, evaluate how far the products are shipped. In LEED 2.1, rewards were given to the use of indigenous and locally manufactured products. Given the global market of lighting, with lamps coming from Eastern Europe and ballasts from Korea, it's hard to say where a lighting product is made. As a suggestion, try specifying products where the final point of assembly is in the U.S. or North America, or if you're really aggressive—within a short distance to the project. When shipped, ensure that the packaging materials are recyclable and require the contractor to follow through. And finally, require the contractor to meet or exceed all LEED-standard jobsite practices.

The recent political climate change is likely to create a new group of novice greenies, as well as ardent politicians, who will seize apparent “sustainable” opportunities to make a point. For example, there is a growing worldwide sentiment to ban the incandescent lamp. (At least one state considering such a ban—Connecticut—had previously worked toward banning mercury-containing lamps). Therefore, it's possible that future laws will dramatically change our choices, and even on a modern project, some popular “sustainable” generalizations will force a variety of lousy design choices.

To prevent the lighting designer's work from “green” misdirection, it is necessary to develop and maintain a current and thorough green perspective. For the foreseeable future, energy and mercury should dominate decisions about lighting. Once these issues are under control, then foray into the wide world of products and all that goes into them. As a guiding light, start with “less is more”—that will be a hard adjustment for our industry, but it's a truly green ethic we need to learn.

Are LEDs Sustainable?

Among the potential benefits of LEDs is the elimination of mercury. But LED lamps pose other environmental issues. Here are several issues associated with LEDs that could tarnish their green halo.

The LED industry has a chance to solve all of this before the problems get out of hand. Let's hope it does.