Characteristics of Sustainable LightingI find the most straight forward and useful way to vision a Sustainable future for a particular problem area is to distill a set of characteristics which describe the vision. These are based not on what we believe to be feasible but as though we were starting from scratch--a blank slate for Sustainability.
- Produce light with (almost) no energy:1)Of course this point is somewhat moot if cheap, clean and plentiful electricity is ever developed (eg cold fusion)--but the mootness applies to lots of our most pressing issues and there is no realistic possibility on the horizon. We have come a long way from the flickering flames of a burning log. But with seven billion people on the planet we need to be producing light with as little energy as possible.2)Going to no energy would obviously violate all kinds of physical laws of our universe.
- Lighting should be accessible to all: In the US, there are very few people (possibly none) who cannot afford to light their dwelling but globally it is estimated that 1.2 billion people don't have access to electricity . Their desire for light is so great that many of them buy dirty, expensive and dangerous kerosene just to be able to see a little at night. In a Sustainable world everyone should have light and if it is expensive or inaccessible it is the poor who will suffer--as they will still have to pay for a minimum amount no matter the price.
- Low/no impact production and disposal: The upstream impacts of production are for many products much larger than the impacts of actual use (eg it is has been estimated that ten times the waste is generated in producing the average product than the actual materials it contains).3)This is a favorite theme of the Lovins and Hawken and why they believe downstream efficiency is so impactful. For lighting though, production impacts are much smaller than use impacts. In addition we must include concerns about end-of-life disposal, particularly in terms of hazardous materials. A truly sustainable product would meet the ideals of Cradle to Cradle .
- Low/no impact in use (outside of electricity): Currently the biggest non-electrical usage impact of lighting is a large amount of excess heat generated which can substantially increase cooling loads. Additionally, bulbs may generate light pollution, require specialized fixtures, impact animal/insect patterns, or any number of systemic type of issues that may be unique to each different technological option.
- Improves Quality of Life: While subjective and variable from person to person, there are several common threads to focus on. The most significant is the light spectrum. Incandescent bulbs do a fairly good job of imitating warm sunlight but while fluorescents have come a long way from the original headache inducing tubes, you won't find many/any people who prefer their light output.4)Research has actually shown clear health impacts of increased exposure to natural light, or light sources that imitate natural light.  There could be various other minor characteristics like dimmability which may contribute to quality of life but one other main issue is that most people don't want to think about their lighting, they just want it to work.5)That is lighting should not increase what is termed our Cognitive Load. Recent research in this area has really emphasize the importance of reducing Cognitive Load.
So What? Finding a Pathway to Our Sustainable Vision for Lighting
Now that we have illuminated our final destination there are two things that we must keep in mind. We should sketch out a path to get to our vision. Sketch a path. Don't pave it. We need to be able to adjust and improve our pathway as technology, knowledge and our goals change. And most importantly, don't wait to figure out the perfect path, take the first step and get moving on the pathway to Achieving Sustainability today!
Next time we'll review how our current options stack up next to our Sustainability vision and gain an idea of what our pathway to Sustainability might look like for lighting.
The Series: Achieving Sustainability in Lighting
- For Lighting, Sustainability is within Reach: But is demand saturated? 
- Achieving Sustainability with Technology: the Exceptional Case of Lighting" 
- When will we be LED to Sustainable Lighting? 
- Bush Era Law is Helping to Achieve Sustainability in Lighting 
- A Vision for Sustainable Lighting 
Footnotes [ +  ]
|1.||↑||Of course this point is somewhat moot if cheap, clean and plentiful electricity is ever developed (eg cold fusion)--but the mootness applies to lots of our most pressing issues and there is no realistic possibility on the horizon.|
|2.||↑||Going to no energy would obviously violate all kinds of physical laws of our universe.|
|3.||↑||This is a favorite theme of the Lovins and Hawken and why they believe downstream efficiency is so impactful.|
|4.||↑||Research has actually shown clear health impacts of increased exposure to natural light, or light sources that imitate natural light. |
|5.||↑||That is lighting should not increase what is termed our Cognitive Load. Recent research in this area has really emphasize the importance of reducing Cognitive Load.|