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A journalism teacher once told me that newspapers should be better than the community they serve. A favorite columnist of mine said the same about libraries. Both offer knowledge, and to be of value, they must enlighten and ideally inspire people to achieve personal growth. This principle applies to education. The intent of this article is to enlighten and inspire further inquiry by teaching new terminology relevant to the lighting professional in 2009. The criteria for inclusion is that these words are not defined in the latest edition of the IES Handbook, published in 2000.
The terms defined below are being assimilated into our vocabulary as a response to changes occurring over the past decade. Lighting professionals were generally not concerned about an energy crisis or carbon emissions 10 years ago. Energy rates were low and no federal energy code existed. The USGBC implemented the first LEED standard in 2000, yet today 10 percent of our new buildings are designed using LEED to minimize the environmental impact of buildings.
Hundreds of communities have adopted dark-sky ordinances over the last decade influencing exterior lighting design often with an emphasis on health concerns from light pollution.
The past decade has revealed our ignorance regarding the effects of artificial lighting on people, plants and animals, compelling us to consider photobiological implications.
Certification programs providing lighting specifiers with credentials for energy management and sustainability are now available. A radical technology shift has occurred toward solid-state lighting. The white LED was not a consideration 10 years ago. Other new ways of generating and enhancing light have been discovered in the past few years.
When the next IES Handbook is written it will need an expanded glossary to include words that help to define the changes in our industry over the last decade. Keep an eye out for the following terms, which should be considered for the 10th Handbook.
• Biomimicry. Biomimicry (from “bios,” meaning life, and “mimesis,” meaning to imitate) is a design discipline that seeks sustainable solutions by emulating nature’s time-tested patterns and strategies, e.g., a solar cell inspired by a leaf or mimicking the process used by turtles to remove salt from sea water. The core idea is that nature has already solved many of the problems we are grappling with: energy, food production, climate control, non-toxic chemistry, transportation, packaging and a whole lot more. Janine Benyus introduced this term in her book Biomimicry and has launched a new website, www.asknature.org, to answer users’ questions about how nature would solve specific problems.
• Biophilia. Edward O. Wilson defined biophilia as “the innately emotional affiliation of human beings to other living organisms.” His 1986 book and others since have focused on human factors research validating physiological effects related to our need to be connected with nature and the outdoors. Our indoor lifestyles with artificial lighting have an impact on our health and attitudes. Studies reveal that even windows can Lighting Research & Education have a positive effect on blood pressure, hospital recovery times, academic test scores and retail sales. The AIA and the USGBC have both held classes on biophilia. Combined with the energy-savings story, this offers another compelling reason for daylighting in buildings.
• Carbon Neutral. This was Oxford Dictionary’s Word of the Year. Their definition: Being carbon neutral involves calculating your total climate-damaging carbon emissions, reducing them where possible and then balancing your remaining emissions, often by purchasing a carbon offset. The offsets referred to are certificates, each representing a reduction of a metric ton of carbon dioxide emissions. They are sold by companies that invest in emissions-reducing projects such as wind farms, biomass energy, hydroelectric dams or forestry projects. They are allowed to sell one offset certificate for every ton they reduce. The USGBC recently announced that if 1 percent of the materials on a project are supplied by carbon-neutral manufacturers, that project meets the qualifications for one Innovation in Design credit. The first manufacturer of carbon-neutral lighting fixtures was recognized in the IES Progress Report (LD+A, January).
• Cradle-to-Cradle Certification. Cradle to Cradle by William McDonough and Michael Braungart is a seminal book for the sustainability movement. The authors present a manifesto calling for an industrial revolution destined to replace traditional manufacturing and traditional environmentalism.
When we recycle a plastic water bottle the plastic cannot be used again for the same purpose because the chemicals added to the plastic create a hybrid product unacceptable for food use. It is actually downcycled instead of recycled and used for a lesser grade plastic such a resin park bench. When that reaches the end of its life it is so low-grade that it is unrecoverable and unusable, ending up in a landfill.
The authors want to eliminate the concept of waste altogether, while preserving commerce and allowing for human nature. They offer examples of corporations that are not just doing less harm—they’re actually doing some good for the environment and making more money in the process. Instead of designing cradle-to-grave products, cradle-to-cradle cycles are perpetually circulated in closed loops maximizing material value without damaging ecosystems. Cradle-to-Cradle certification offers a company a chance to differentiate its products in the marketplace. The first lighting manufacturer to have a product attain the new certification was recognized in the IES Progress Report.
• Organic Electronics/OLED. OLEDs are self-luminous, flexible, paper-thin light sources. They are considered part of a growing category of sources called organic electronics. Essentially, the OLED consists of two charged electrodes sandwiched on top of some organic light-emitting material. Efficacies are now reported at up to 102 lumens per watt with a rated life of up to 20,000 hours. The organic component degrades when exposed to oxygen but as better techniques of sealing them are developed the life is expected to lengthen.
There are two forms of OLED displays: passive-matrix and active-matrix. The active-matrix is used for high-resolution images such as in Sony’s new OLED television set which has higher definition than Blue- Ray and uses a fraction of the energy consumed by LCD and Plasma displays. The basic OLED cell structure consists of a stack of thin organic layers sandwiched between a transparent anode and a metallic cathode. When an appropriate voltage (typically between 2 and 10 volts) is applied to the cell, the injected positive and negative charges recombine to produce light (electro luminescence). The structure of the organic layers and the choice of anode and cathode are designed to maximize the recombination process in an emissive layer, thus maximizing the light output from the OLED device.
• Quantum Dots/Carbon Nanocrystals. In 2005, quantum dots, which are crystals generally only a few nanometers in size, were discovered to be able to glow with a white light. One of the lighting applications uses very small carbon crystals clustered around blue LEDs. About 85 percent of the energy produced by the blue LED is heat. The carbon soaks up the long wavelengths typically lost as heat and radiates light outward shifting them into shorter wavelengths in the visual range increasing the efficacy at least two times. Quantum dots contain anywhere from 100 to 1,000 electrons. They’re easily excited bundles of energy, and the smaller they are, the more excited they get. In addition to improving the efficacy of LEDs, quantum dot mixtures could be painted on just about anything and electrically excited to produce a rainbow of colors, including white.
• Sonoluminescent. Sonoluminescence is the process of turning sound energy into light. An ultrasonic horn is used to resonate a bubble of air in a medium, usually water. The bubble is ultrasonically compressed collapsing into a light-emitting plasma. In the general physics community, sonoluminescence studies are being carried out to better understand it and to uncover its practical uses. Wavelengths now are mostly blue and in the UV range. The potential of this new light source for architectural lighting applications will be revealed in the near future.
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