Photos of old lighting, left, with new LED street lights on the right.
While there are many benefits to LED streetlights, there are some downsides too. They only provide directional light, so they can't produce a spherical "glow" emanating in all directions, like most lights. Because of this feature, they are generally used in streetlights that are hanging or facing downward, rather than in lamp-type lights. Still, they are considered well-suited to outdoor applications and some people have appreciated the directional light, as it doesn't cause streetlights to shine into homes or create light pollution by shining light into the sky where it's not needed.
The initial cost of LED lighting is high, and consequently, it can take several years for the cost difference to be made up through cheaper energy bills. An LED streetlight costs around $1,000, while standard lights cost $250 each. Similarly, a 60-watt fluorescent bulb for a home lamp can be purchased for $1, with a similar compact fluorescent bulb costing around $2. But an LED bulb, produced by Phillips and designed for home use, costs $107. The high cost derives in part from the material used: LEDs are often made on sapphire or other expensive substances.
Some users have been disappointed in the brightness of LEDs. But new technological developments have LEDs closer to producing classic bright white light. Eventually, LEDs are expected to be able to produce all colors of the spectrum, but for now, they are generally limited to red, yellow, green (hence their use in traffic lights), blue and a white that bears a slight blue tint [source: Britt].
While cities are trying to think long-term and, in the United States, seeking stimulus money to help fund LED streetlight conversions, the cost may be prohibitive for some municipalities. In light of the recession, some cities are turning off existing streetlights to save on electrical bills. Others are looking into adding motion sensors that activate streetlights only when pedestrians are detected.
Finally, some experts think that though many cities are interested in LED streetlights, the greatest barrier to widespread adoption of the technology may simply be education [source: McClear]. Many people are unaware of the many uses of solid-state lighting, as LEDs are classified, and that high initial costs can lead to long-term savings. But with companies like Phillips investing millions in research and development and clamoring for valuable municipal contracts, LED streetlightscertainly have a bright future.
Amidst all the hubbub about tackling global warming and cultivating green energy, one subject receives little coverage: 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" [source: Rosenthal and Barringer].
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.
The initial cost of LED lighting is high, and consequently, it can take several years for the cost difference to be made up through cheaper energy bills. An LED streetlight costs around $1,000, while standard lights cost $250 each. Similarly, a 60-watt fluorescent bulb for a home lamp can be purchased for $1, with a similar compact fluorescent bulb costing around $2. But an LED bulb, produced by Phillips and designed for home use, costs $107. The high cost derives in part from the material used: LEDs are often made on sapphire or other expensive substances.
Some users have been disappointed in the brightness of LEDs. But new technological developments have LEDs closer to producing classic bright white light. Eventually, LEDs are expected to be able to produce all colors of the spectrum, but for now, they are generally limited to red, yellow, green (hence their use in traffic lights), blue and a white that bears a slight blue tint [source: Britt].
While cities are trying to think long-term and, in the United States, seeking stimulus money to help fund LED streetlight conversions, the cost may be prohibitive for some municipalities. In light of the recession, some cities are turning off existing streetlights to save on electrical bills. Others are looking into adding motion sensors that activate streetlights only when pedestrians are detected.
Finally, some experts think that though many cities are interested in LED streetlights, the greatest barrier to widespread adoption of the technology may simply be education [source: McClear]. Many people are unaware of the many uses of solid-state lighting, as LEDs are classified, and that high initial costs can lead to long-term savings. But with companies like Phillips investing millions in research and development and clamoring for valuable municipal contracts, LED streetlightscertainly have a bright future.
Amidst all the hubbub about tackling global warming and cultivating green energy, one subject receives little coverage: 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" [source: Rosenthal and Barringer].
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.
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