Is It Time to Rethink Quality in Lighting?

The lighting industry is strongly fixated on the concept of quality—it’s central to advocacy efforts,  unites the profession, and is embedded in incentive programs that promote sustainability and energy efficiency. This emphasis on quality has been critical for fostering the adoption of energy efficient lighting technologies. However, tackling the broader environmental impacts of lighting might call conventional wisdom about quality into question, particularly for lighting hardware.

Quality of Lighting Products

Lighting professionals generally agree on the range of characteristics that determine the quality of lighting products (e.g., luminous efficacy, lifetime, color quality, power quality, temporal stability), though measurement challenges and disagreements about the operationalization of some traits remain. With the understanding that the particulars of certain attributes are application-specific (especially regarding color), the general thinking is that more is better: higher efficacy, longer lifetime, increased stability.

Sustainability Beyond Energy Efficiency

Although concerns about the substances used in modern lighting technologies, how they are obtained, and how they are eventually disposed of are not new, Brad Koerner’s winning submission to the U.S. Department of Energy’s Sustainable Manufacturing of Luminaires Prize highlighted the broad range of materials used in luminaires that ultimately affect the environment. To minimize embodied energy and enable safe disposal, this design uses lightweight, biodegradable materials, including a compostable printed circuit board. Although this is clearly a nascent technology with little performance data available, components that are specifically designed to eventually degrade contrast sharply with the lighting industry’s long-standing emphasis on developing the most robust, long-lasting products possible.

Too Much Quality?

To investigate the usefulness of one key measure of product quality (lifetime), different operating duration and frequency scenarios can be used to approximate the longevity of an LED luminaire with an estimated life of 50,000 hours, and then compared with survival data on newly established businesses from the U.S. Bureau of Labor Statistics.

Table 1. Operating and Duration and Frequency Scenarios for LED Luminaires vs. Operating Years of Businesses

(Source: Guidehouse Insights, U.S. Bureau of Labor Statistics)

The results are even more striking for residential applications. Since the average daily operating time for light sources in homes is estimated to be 1.6 hours, a luminaire with a 50,000 hour life can be expected to last for more than 85 years!

Modern lighting products are clearly capable of outliving many of their owners. At best, consumers investing in quality luminaires are unlikely to realize the full benefit of their investment. At worst, many lighting products will end up in landfills before they reach the end of their functional life. 

Thinking More Holistically

A number of strategies are useful for minimizing the materials-related environmental impact of lighting hardware, including design for disassembly and effective recycling programs. Nonetheless, current notions of product quality may be stifling the industry’s ability to develop the most net beneficial products.

Although this is relatively simple to illustrate with product lifetime, all product quality indicators warrant interrogation. Even the indirect consequences of product design decisions made to maximize characteristics as crucial as luminous efficacy should be identified, quantified, and scrutinized in relation to real-world product use. Choices about materials and manufacturing processes have a range of effects (e.g., resource consumption, pollution) that must be weighed against the improvements they enable. It can seem blasphemous to those that helped LEDs achieve such remarkable performance, but, for many applications, the highest quality products may not actually be best.