Monday, December 13, 2010

Los Angeles Going Dark Sky Compliant

by Wendy Kahler, U.S. Embassy Helsinki Environment, Science and Technology Officer

In March 2003, astronauts on the International Space Station snapped a photo of Los Angeles at night. From 240 miles away in space, the city of 498.3 square miles (1,290.6 km2) and 3.9 million people looks like a giant luminescent fish. When Thomas Edison invented the light bulb in 1879, he never expected his little balls of light would illuminate entire cities bright enough to be seen from space. It’s a technological marvel, and increasingly an environmental headache.
The City of Los Angeles has over 200,000 street lights in its control generating nearly 170,000 metric tons of carbon dioxide every year – roughly the equivalent of 9500 cars on the road. The city’s lights also contribute to nighttime light pollution known as sky glow that blots out the stars and disrupts the natural patterns of nocturnal animals.
In an effort to reduce its carbon footprint, the “City of Angels”, in partnership with the Clinton Climate Initiative, has begun replacing 140,000 of the city’s streetlights with LED (light-emitting diode) fixtures. LED’s are small semiconductors that generate light when applied to a current. Compared to traditional light fixtures, LEDs have a number of advantages. LEDs use a fraction of the energy to produce a lumen (brightness) level comparable to regular bulbs. Lacking a standard bulb’s delicate filament, LEDs have near zero fail rates and are particularly well suited for outdoor uses such as street lighting. Many LED fixtures last for 50,000 hours, or nearly 11.5 years when operated 12 hours per night. In addition, the direction of LED light is more precise nearly eliminating the wasteful sideways and overhead spillage produced from traditional lights which contribute to sky glow.
Los Angeles Mayor Villaraigosa launched the streetlight retrofit in 2009 as part of the city’s GREEN LA initiative to reduce its greenhouse gas emissions 35% below 1990 levels by 2030 and increase its renewable energy to 40% by 2020. The retrofit will take five years and is divided into five year-long phases. In 2009, 20,000 fixtures were replaced with LEDs. Starting in 2010, 30,000 light fixtures will annually be upgraded to LEDs for a total of 140,000 new fixtures throughout the city by 2013.
Since LED technology is evolving rapidly, the retrofit’s phased roll-out allows project coordinators to continuously reassess which LED products would best suit the city’s needs. The upgrade also includes a remote monitoring device, which will allow the Los Angeles Bureau of Street Lighting to monitor each fixture’s performance level using real-time data.
Of course all this new technology doesn’t come cheap. The estimated total cost of the retrofit project is $57 million. However, once the project is complete, Los Angeles can expect an annual energy savings of 68,640,000 kWh per year. This translates into an annual energy and maintenance savings of $10 million and full pay-back on the city’s initial investment within seven years.
And the city’s carbon footprint? The 140,000 LED fixtures will reduce the city’s CO2 levels by approximately 40,500 tons per year – the equivalent of 6500 passenger vehicles. That sort of impact has others taking notice. US cities from Ann Arbor, Michigan and Anchorage, Alaska to Pittsburgh, Pennsylvania are moving forward with their own LED retrofits to meet their climate goals.

US Embassy Helsinki is also doing its part. Under Ambassador Oreck’s direction, the Embassy has replaced all its outdoor security lighting with new LED fixtures. Several of the light fixtures in the Ambassador’s residence as well as the holiday Christmas lights have also been upgraded to LEDs. The new installations are expected to significantly reduce the Embassy’s annual energy costs.
Every effort counts when it comes to living more sustainably and LEDs lights are an easy way to make a big impact. The view from the International Space Station may get a bit dimmer, but the future of the planet is now looking a lot brighter.


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