streetlights. While an important public service, streetlights are expensive to maintain and taken together, suck down a lot of energy. So when a city like Los Angeles announces that it's converting 140,000 streetlights to light emitting diodes or LEDs, and Pittsburgh states that it's considering doing the same with 40,000 lights, it's time to take notice.
LEDs are gaining traction as a great alternative to traditional lighting because they are relatively environmentally friendly, don't consume much electricity and have long life spans. They last so long -- 14 years or more in some cases -- that they can be considered "semi-permanent"
Some of the world's biggest electronics firms are now touting LEDs as the next big thing in lighting, whether in a small appliance or the biggest skyscrapers. By 2013, the LED market, which covers anything from holiday lights to those on the Empire State Building, is expected to be worth $1 billion [source: Rosenthal and Barringer].
In the past, LED lights had been seen in devices like indicator lights in appliances, calculators or in large sports scoreboards. But now, many large cities around the world -- Los Angeles, San Francisco, Toronto and Tianjin, China, to name a few -- are now switching to LED streetlights. Portugal is in the midst of a massive conversion program that is expected to encompass all of its streetlights.