The San Francisco Public Utilities Commission announced in April that it plans to replace 18,500 of the 25,000 high-pressure sodium streetlights it owns in the city with more efficient LED ones.
The city organ promises “the new LEDs will improve lighting conditions throughout the city and will last about four times longer than existing lights while using half as much electricity.”
According to the U.S. government’s Energy Star program, LEDs (light-emitting diodes) are:
Directional light sources, which means they emit light in a specific direction, unlike incandescent and compact fluorescent bulbs, which emit light and heat in all directions. For this reason, LED lighting is able to use light and energy more efficiently in many applications.
Perhaps more notably for residents, SFPUC says the new lights will operated with “a color temperature of 3,000 Kelvin” and “will emit warm, white light” instead of the yellowish sodium glow of existing lamps.
This means the look and mood of the city’s nighttime streets will change. LED manufacturer Lighting Science claims that LED lights boast “superior color accuracy ... Unlike [sodium] lamps, they consistently display the natural colors of an illuminated environment.”
On paper this is a good thing—it increases visibility, which of course is the entire point of a streetlamp.
But as SF Weekly notes, many San Franciscans, visitors, and photographers have gotten used to the yellowy hue of the old lamps. The more intense LED illumination may lack the atmosphere of the existing lighting scheme.
Here’s a side by side comparison of a similar changeover in LA:
Not every light will change, and SFPUC doesn’t even operate every light in San Francisco. The agency produced a handy map for those curious—or concerned—about their local level of illumination.