The companion blog to the books Designing With Light and Fundamentals of Energy Efficient Lighting and Controls
So…Wiley has had some trouble with this book’s section of their web site. To make things easier for students I’ve added a Resources section to this site with PDFs of flashcards, brief self-evaluation tests, and a few calculators. Just click on the Resources tab above. The only things missing are the animations that are reference in the book. Unfortunately, I can’t find a way for WordPress to host interactive components, but everything else is just a click away. You’re welcome!
The Department of Energy (DOE) has extended the comment period for proposed energy efficiency standards for general service lamps (GSLs) until February 23, 2015. Documents associated with this set of standards are Docket No. EERE-2013-BT-STD-0051. There is a link on that page to submit comments.
You may recall that the Energy Independence and Security Act of 2007 (EISA) set minimum efficiency standards for medium screw base (a.k.a. E26) general service lamps (a summary of requirements and exemptions is here). Those minimum standards were phased in by wattage and now cover GSLs from 40 to 100W. Decorative and other specialty lamps are excluded. A public meeting and webcast was held on January 20th to explain the new standards for consumer lamps. You can download a PDF of the presentation here. It’s a long presentation of 94 slides, so here’s a summary.
1. The DOE is considering establishing standards for the following lamp types:
2. The DOE is considering requiring the following lamps, which are currently exempted from EISA requirements, to comply with the new standards:
3. The DOE is also considering not setting standards for certain lamp types for reasons that include:
There are over three dozen identified issues that are open for comment. These standards will have a far reaching effect, so I urge you to look over the presentation and submit comments.
The spring semester starts this week for my Pratt students and next week for my Parsons students. The beginning of the semester is always a little hectic and stressful. Here’s a bit of fun to take the edge off. Not many forms of energy have their own song. Here’s “Electricity” by Orchestral Manoeuvres In The Dark (aka OMD). It’s so painfully dated that it’s funny.
By now you have, no doubt, seen the headline that 2014 is the warmest year since reliable record keeping began in 1880. This was jointly announced by two US agencies – NASA and NOAA – and corresponds with an announcement by a similar agency in Japan. I’m not going to retell that story here, but I do want to repeat some of the most alarming points.
Here’s a graph illustrating the trend.
For those who think that climate change is a liberal conspiracy, my suggestion is to take it up with the Pentagon. In 2012 the Pentagon formed a climate change working group. The result of their work is the DOD 2014 Climate Change Adaptation Roadmap, which was released in October 2014 and accepts climate change as a fact. About the report, Defense Secretary Chuck Hagel said that “Politics or ideology must not get in the way of sound planning.”
The New York City chapter of the IES will host a presentation by Mariana Figueiro and Leora Radetsky of the Lighting Research Center titled “Swimming in an Ocean of Light: Using Light for Health and Well-being.” The program will include the IES Light and Health seminar, which they co-authored, as well as updated material with recent research results and their insights about “turning research into design practice.”
If you’re interested you can RSVP here.
The United Nations has proclaimed that 2015 is the International Year of Light and Light Based Technologies, also referred to as IYL 2015. 2015 is the anniversary of quite a few notable discoveries about light. The UN resolution recognizes “the works on optics by Ibn Al-Haytham in 1015, the notion of light as a wave proposed by Fresnel in 1815, the electromagnetic theory of light propagation proposed by Maxwell in 1865, Einstein’s theory of the photoelectric effect in 1905 and of the embedding of light in cosmology through general relativity in 1915, the discovery of the cosmic microwave background by Penzias and Wilson, and Kao’s achievements concerning the transmission of light in fibers for optical communication, both in 1965.”
By focusing on the topic of light science and its applications, the UN hopes to raise global awareness about how light-based technologies promote sustainable development and provide solutions to challenges in energy, education, agriculture and health. It’s an exciting idea, and I hope that we see a lot of activity surrounding light and lighting design in the profession, allied professions, and the media. It’s a great opportunity for the IALD, IES, manufacturers, etc. to raise their profile, raise the profile of lighting design, and educate people about the advantages of well designed lighting. Unfortunately, as of today very few activities have been announced and none of them are activities or events related to lighting in the built environment (not counting annual events, such as LightFair, that would happen anyway). If you have any contacts within these organizations, urge them to take advantage of this special year.
No family get together or holiday party is complete without a yule log. Here’s one…
The main design assignment for this semester’s Pratt students is a cafe. The students selected their own interior design and had to develop a custom lighting fixture that is integrated with that design. Here area few of this semester’s fixtures.
The Lighting Research Center at Rensselaer Polytechnic Institute recently published a short video in which LRC director Mark S. Rea discusses the costs and benefits of lighting. Here it is.
If you set aside the plugs for the LRC, his statements, and those in his book Value Metrics For Better Lighting, are similar to what I’ve said throughout Designing With Light, which is that it’s the quality of the light and lighting design that are of primary significance while the amount of light that is delivered is secondary. Therefore, the true value of the lighting design is found in the design’s success in meeting the multiple requirements of the owner and the occupants of the space, not in the cost of hardware and installation.
Unfortunately, there are several factors that have created resistance to placing value on thoughtful, appropriately designed lighting. The first is that most people simply do not see light (pun intended). For far too many people, if the light is bright enough for them to see what they’re doing it is acceptable and little or no judgment is made regarding the other factors of lighting design, such as color rendering, providing visual interest, overall effect on occupants, etc. I find that if I show clients or students the difference between light that is adequate for vision and light that creates an appropriate atmosphere or environment they can see it and appreciate the difference. It is also a surprise to them that lighting design can make such a difference in a space.
The second factor is that project budgets are set in dollars with no little or no allowance made for the quality of the design. I have often worked on projects where the project budget and the lighting equipment budget have been set, although design work has barely begun. I understand that a client only has so much money to spend and that has to be respected. However, 1) No bean counter in the world can predict what the design team will develop. Budgets are more appropriately set in coordination with the design team after the design team understands the full extent of the client’s needs and desires. Then, if the projected cost exceeds the client’s budget, informed decisions can be made to pull back on certain aspects of the building’s design or to allocate more money to construct the building the client wants. 2) Spending more money up front on efficient lamps and fixtures, and on controls, can more than pay for itself in savings on energy and maintenance.
Another factor is that we value what we can measure. Since the early 1900s the lighting design community has invested a great deal in determining how to measure light and on how much light is required for “visual tasks.” Those two aspects became the criteria for evaluating lighting design, and are still presented as primary in many lighting textbooks. In the 1970s John Flynn and others began to study how light can affect the impressions one forms of a space. Later research examined the relationship between a lighting design and those occupying the lighted space including: the affect on worker productivity, absenteeism, and worker retention; student learning outcomes and test scores; retail sales; a light source’s spectrum and clarity of vision; and light’s affect on sleep cycles and other aspects of health. This research has shown over and over again that intelligent, thoughtful, appropriate lighting design can have a significant effect on the occupants and on the owner’s bottom line, whether that bottom line is to make more money, increase student success, or improve health.
Knowledgeable lighting designers can bring so much more to a building than just illumination, yet illumination and lighting design remain synonymous to most of our colleagues and clients. That is part of the reason only about ten percent of construction projects have a lighting designer on the team. Lighting designers and lighting design professional organizations need to do a much better job of educating design team members and our clients about quality lighting design, what it is, and why it matters.
NPR’s All Things Considered had a brief piece about light and color on Monday. The main thrust of the story was that color is not inherent in an object, but is perceived and interpreted by our brain, but there’s much more to revealing and perceiving the color of objects. Here’s a quick overview.
To begin, all objects have light reflecting properties. Objects that we identify as red reflect most of the red light that falls on them and absorb the other colors. Likewise for objects that appear to be green, blue, etc. Objects that appear to be white reflect the colors of light more or less equally, while objects that appear to be black absorb most of the light that falls on them. Objects only reflect light, they don’t create it, so if we use blue light to illuminate an object that reflects red light we find that no light is reflected and the object appears to be black.
As I explain in Chapter 8, we change the balance of the colors in white light every time we change the light source. Even with a single light technology, such as fluorescent, we change the balance of colors when we change from cool white to warm white. The color content of a light source can be measured (it’s called the spectral power distribution or SPD) and graphed as shown below.
When we change the SPD we change the colors of light that are available for reflection by objects, which means that we also change the balance of light that is reflected and thus the color information that our eyes receive. The result is that changing the light may change the color appearance, or the apparent color, of an object. Many of us have had the experience of buying clothing or paint that was one color in the store and another color at home. Here we see this phenomenon with a color/materials board illuminated by several light sources. How well a light source enables us to perceive colors is called color rendering.
Color and brightness perception are both relative not absolute. A candle in an otherwise dark room may seem too bright to look at directly, while its brightness on a sunny day seems insignificant. In addition to the effect of SPD on our color perception, colors are perceived in relation to one another, especially between foreground and background as shown below.
If I can demonstrate shifting our color perception why don’t we experience it in everyday life? Why are my blue jeans blue and my red car red in nearly every lighting situation? The answer is color constancy or chromatic adaptation. It does us no good to spend time and energy struggling to figure out colors. We want to be able to tell if a piece of fruit is ripe regardless of the lighting conditions. Color constancy is our brain’s use of information gathered from the entire visual field to understand the lighting conditions and calibrate our color perception so that color shifts are minimized.
