LED street lights to be rolled out across Northern Ireland in bid to save money
A scheme to introduce LED street lights in Northern Ireland in a bid to save money and reduce light pollution is to be rolled out across the province.
There is currently 300,000 yellow sodium street lights across Northern Ireland.
The Department for Infrastructure (DfI) started a switch to LED alternatives with a pilot scheme in Banbridge and Armagh in 2015, and that is now being rolled out across Northern Ireland.
DfI officials say the new lights offer long-term savings in electricity usage and maintenance costs, as well as less light pollution.
It is claimed LED lights are 50% more energy-efficient than traditional yellow sodium lights and last up to 20 years.
The BBC reports around 50,000 of the new lights have been installed so far.
Michael Burton, Armagh Planetarium and Observatory director, told the BBC that while LED lights make the stars easier to see in an urban area, they may present other challenges.
"What's important is to try and have LED that have what we call warm colours, which come in the red part of the spectrum," he said.
"Lights in the blue part of the spectrum - cool colours - were bad for the eyes," he said.
"They don't adapt when you are outside and you really can't see the stars," added Mr Burton.
"If it is in the red part of the spectrum they will adapt and you'll be able to see the stars and the streets as well.
"It is quite complex. Sodium street lights emit all of their light in very narrow lines, very specific wavelengths."
Lara Trainor, lecturer in health science at Ulster University, said exposure to LED light at night time can make sleeping more difficult.
"It can affect the melatonin in the body, which is the sleep hormone and which plays a part in the circadian rhythm," she said.
"So you won't sleep as well if you are exposed to them."
She added: "It is really important that people have good sleep hygiene; that they aren't exposed to light before they go to bed - whether that is TVs, phones, laptops or computer screens.
"Also, if they are exposed to the LED lights they should have black-out curtains or blinds to reduce the effect on the circadian rhythm.
"Unfortunately for people who are homeless or for animals, they don't have that option so it will affect them more than someone who is living in a house."
Belfast Telegraph Digital