LED streetlights may be at the core of the 'smart cities' of the future, but they are also at the centre of ongoing health debates, one of which is that LED light can allegedly cause blindness.
That has pressured some towns and cities to address those concerns. In Derbyshire the county council has an answer for anyone worried that the county's soon-to-be 70,000 new LED lights will rob them of their vision: It's not true.
'The intensities used within street lighting are insufficient to cause harm,' says Mike Ashworth, strategic director for transport, in an article in the Derby Telegraph.
A 2013 study at Complutense University in Madrid found that the blue light emitted by light emitting diodes – common in computer and gadget screens and increasingly in energy saving home and outdoor lightbulbs - can irreparably damage the retina, a finding that the press turned into a blindness scare.
That would be bad news for Derbyshire, which is planning to spend £10 million to convert 68,796 conventional streetlights to LEDs, and to spend another £13 million replacing 22,000 aging columns, according to the story.
In a reassuring paper to cabinet members, Ashworth notes that, 'The possible health and ecology risks are considered to be minimal and could be managed through monitoring and through the careful selection of products.'
Derbyshire expects the project to save at least £1.2 million a year in energy bills, and is considering retrofitting additional conventional lights – the nearly 70,000 represents about 78 percent of the county's total.
The council earlier this year also decided to turn off 40,000 streetlights between midnight and 5:30 a.m. to save money, a measure that other British localities are taking, sparking great controversy.
The blue spectrum of LED light has also been linked to sleep abnormalities and to cancer.
Many cities are relying on LED streetlighting not only as a way to save energy, but also as a foundation for intelligent data networks that underpin the operations of 'smart cities.' LEDs are semiconductors that lend themselves to digital comunications. Thus, lamps equipped with sensors could be used to transmit information about traffic, crowds, air quality and other things.
An collaborative experiment outside of Copenhagen is helping to advance the concept. In one novel use, Los Angeles is considering flashing LED streetlights to help direct fire and police crews to emergency scenes.
Photo is from Paul Daniels via Shutterstock
Want to sound off on LED streetlighting? Come to LuxLive2014 Nov. 19, 20 in London, with lively sessions debating LED street lighting and more. Meanwhile, the European Commission is assembling mayors, city managers and vendors next week in Rome to debate the way forward in smart lighting. Lux will run the spirited discussion. We can't wait to tell you about the inventive ideas.