January 28th, 2008
Through a program of such awards, publications, guides, and conferences, IDA not only promotes good lighting practices but helps manufactures design, and consumers select, sensible lighting fixtures. (Manufacturers of such fixtures can apply for IDA’s dark-sky friendly seal of approval and be cited on the group’s list of lights that meet its standards.)
Sensible means fixtures that are “full cutoff,” or shielded. Fully shielded lights use reflectors — less often flat-bottom lenses — to direct illumination downward, to the street or pathway or front steps where it’s needed. None of the light is visible above the horizon line.
Because they waste less light, full cutoff fixtures can use bulbs of lower wattage, thus save energy. When Calgary, Alberta, retrofitted its 37,500 streetlights with full cutoff fixtures and reduced wattage, that city saved more than $1.5 million a year in energy costs. A similar project in San Diego has saved $3 million a year.
Even malls, superstores, shopping strips and other businesses are starting to get the message, says Dr. Crawford. Can private homes be far behind?
<--Previous : : Next Page-->
