Avoiding skyward illumination
Light pollution has become a public awareness issue and the International Dark Sky Association (IDA), is a powerful advocate for restricting light pollution.The IESNA is working with IDA to draft a model exterior lighting ordinance.
Regulating Lighting Design
Lighting design is regulated in most states by defining the maximum allowable number of watts per square foot. This is called "lighting power density" (LPD).
Lighting power density is a major constraint in lighting design.
Building codes are not uniform across the country.
While all states are required to have codes governing LPD many do not police or enforce the limits.
The current trend, however, is for more strict energy code enforcement during planning, inspection and even after occupancy.
Sustainability Home Page
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Sustainable Lighting Defined
The current working definition of sustainable lighting is,
"Lighting that meets the qualitative needs of the visual environment with the least impact on the physical environment.
"Illuminating Engineering Society of North America, Sustainability Committee, 2001.
Lighting quality is the primary goal of sustainable lighting design.
That may seem to be contrary to
having the least
impact on the environment but the two aspects of the definition,
lighting quality and minimum impact, are not mutually exclusive. Often
providing quality light minimizes the amount of energy used.
You have checked into hotels and turned on every light in the room to be able to live comfortably. The innkeeper thought he was going to save a bundle by buying the cheapest compact fluorescent he could find and using a lower wattage than required. We need to use more inferior light and therefore more energy to compensate for the lack of quality light.
Meeting the qualitative needs of the visual environment is the primary objective for sustainable lighting because quality lighting means productivity. Time and time again it is proven that quality light that makes humans feel good means more productivity. Quality is both the amount of light and how well the light source renders colors. In the office environment good color rendering makes humans look better, feel better, and accomplish more work. It is as simple as that.
Quality lighting is all about color in the retail environment.
Certainly 
you would agree that good color
rendering is important for
fashion or furniture. But it is just as important to groceries
and auto
parts. Why else would grocers put the most expensive light source in
the produce and bakery departments? Why else would auto parts stores
buy the
best fluorescent tubes rather than saving a buck? In each case the
merchant knows the importance of quality lighting to the way customers
perceive the store and its products.
Meeting the qualitative needs of the visual environment in retail means sales. We are not after the cheapest light source but the one that meets the needs of the visual environment with the least impact on the physical environment. "Least impact" generally means "Lowest total cost of ownership" so the approach fits as part of the businesses overall sustainability strategy.
A Sustainable Lighting Design Includes:
A sustainable lighting design in today's world means using daylight, optimizing the use of energy, ensuring lighting system durability and reducing operating costs.
Lighting is part of an overall sustainability strategy.
It is 
one of the easiest areas to
improve in existing
buildings but other energy saving opportunities should not be
overlooked. Lighting may be 25% to 40% of a retail electricity
bill so
60%-75% is
consumed by something else. HVAC is usually the lion's share but we
should not
overlook "plug load."
Plug load in a furniture store would include table lamps on display. That is an important part of merchandising but is generally something the lighting designer takes into account. By replacing a standard incandescent with a compact fluorescent the table lamp plug load can be reduced by 78%.
Raymour & Flannigan went the additional step and replaced all CRT computer monitors with LCD monitors to reduce plug load. Your sustainability strategy needs to be comprehensive.
Maximizing Daylight Harvesting
New construction will use daylight whenever possible. Skylights are mandatory in California for any building 25,000 square feet or more. There are ways to control the amount of light and heat coming through what amounts to a hole in the roof but natural light is a primary source for interior lighting.
Humans enjoy natural light so having an office with windows for natural light is a measure of status. Evidence is starting to show that the presence of natural light increases sales, student performance, and employee health.
To take advantage of daylighting we need to dim electrical lighting. This is called daylight harvesting. As daylight increases in intensity a balance is achieved with sensors and dimming ballasts. As is often the case with sustainable lighting, sensors and dimming ballasts cost more initially but quickly pay for themselves through energy savings. Electrical lights can often be turned off entirely in large, open buildings. Maintenance hangars, warehouses and super centers as we will see are examples where daylight harvesting can be used.
Optimizing Energy Use
Optimizing the use of energy is a common practice for lighting
design. Our intent is always
getting the most light output
for the
least light input with the right type of lighting source.
That means in most cases we could replace metal halide fixtures in warehouse, factory, or big box retail buildings because they are diffuse sources providing ambient light. Conversely, we would not replace halogen accent lights with fluorescent because the halogen is a point source. Even though the fluorescent is more efficient, greater lumen output per watt, the quality of the light produced is not suitable for the intent of product highlighting.
Our use of energy for lighting is not minimized. Rather, energy use is optimized.
Ensuring Durability and Maintainability
Lighting design is the selection and arrangement of luminaires to meet the needs of the visual environment. A luminaire is the combination of a fixture and a lamp. Each has characteristics that define durability and maintainability.
The lighting fixture must be easy to maintain over its life cycle and must be durable enough to withstand service for the life of the structure. Fixture maintainability minimizes the service required but when required allows for minimum service time. Maintenance examples would be replacing a lamp or ballast with no tools required.
Light bulbs (Lamps in the lighting industry) require frequent replacement so service life is a major concern for the lighting design. The longer the service life the better provided the lamp retains lumen output. Lamps "depreciate" over their service life meaning that initial output is higher than the output near the end of life. Metal halide lamps typically have greater depreciation that other type of lamps. Ceramic metal halide on electronic ballasts have better lumen maintenance.
Sustainable Lighting Reduces Operating Costs
The second part of our
definition of sustainable lighting is,
"minimizing the impact on the physical environment." In simple terms
using fewer resources means lower operating cost. That is good for
business but it is also a necessity in today's regulatory environment.
New energy code requirements have come out every year in one form or another since 1992. The overall lighting guide is prepared by the Illuminating Engineering Society (IES) and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). These two organizations have created the benchmark lighting standard known as 90.1. That standard is incorporated into the International Energy Conservation Code cited by many states as the standard for residential and commercial construction.
The Advanced Energy Design Guide series prepared by ASHRAE, the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IES), and the U.S. Green Building Council (USGBC), with support from the Department of Energy (DOE). The guides are available for download and provide recommendations for off-the-shelf technology to achieve 30% energy savings beyond the minimum requirements of ANSI/ASHRAE/IESNA Standard 90.1-1999, Energy Standard for Buildings Except Low-Rise Residential Buildings.
The New Buildings Institute (NBI) was founded in 1997 to promote improved energy performance in commercial new construction. They have updated Advanced Lighting Guidelines for 2003. The publication contains a comprehensive discussion of lighting concepts and commercial lighting design.