As thousands of old-school sodium street lights across Bermuda get replaced with energy-saving LED fixtures, the island stands to halve its budget for illuminating the roads.

But not everybody welcomes the move, with one West End resident complaining that the new lights force him to squint — and goes beyond a threshold set by the American Medical Association after widespread complaints in the United States.

Bermuda had its own case in 2011 when Global House was fitted with 1,300 LED lights that were so heavily blue-tinted that the entire system had to be replaced.

Under a contract sealed with the Bermuda Government in May 2015, Belco is replacing about 2,000 sodium lights with LED technology, a programme slated to take two years.

According to a Belco spokeswoman, the government-financed programme will “contribute greatly to national energy efficiency and conservation goals, including reducing fuel consumption and carbon emissions from street lighting by approximately 57 per cent”.

About 1,800 street lights have been switched, covering 95 per cent of the island’s main roads.

Calling the public response “positive”, the spokeswoman said that when 98 residents had been polled after the lighting went up around Trimingham Hill, 80 per cent felt that LEDs improved street lighting.

However, “I find it much too white, too glaring,” said the anonymous member of the 20 per cent against.

“I like to go walking at night, and I find it very hard on my eyes. I have LED lighting in my house, but it’s a yellower kind of light, which doesn’t trouble my eyes. I guess it’s too late to change the lights now, but I have to say I don’t like them.”

In the US, where many cities have embraced LED street lighting, the American Medical Association has cautioned against extra bright fixtures.

Over the summer, the AMA recommended that communities adopt lighting with a “colour temperature” set at 3,000 Kelvin.

Colour temperature refers to the spectrum of light. The higher the CT rating, the greater the content of blue in the light, making it harsher — the same problem that emerged in Global House, where many workers complained of the “cave effect” induced by the lights.

Aside from the glare, the bluish light scatters more easily in the eyes, making it more difficult to see — and interfering with the body’s production of melatonin, the hormone that controls sleep. Glaring lights have also proved disturbing to wildlife.

The problem was severe enough that some American cities, such as Seattle and New York, ended up taking down their new LED systems, and replaced them with friendlier illumination tailored to the red and yellow end of the spectrum, better suited to human eyes.

The Belco spokeswoman said the company was aware of the AMA advisory, which included shielding lights to minimise glare.

“Blue light is emitted by many sources aside from LED street lighting, including indoor LED lighting, fluorescent lighting, televisions, mobile phones, tablets and regular incandescent light bulbs,” she said. “And some of the sources provide much higher levels of light in homes than street lights do.”

The US Department of Energy has come out in favour of LEDs, she added — in particular, for the ability to dim them where appropriate, which is virtually impossible with conventional street lighting.

LEDs also offer a high degree of control over the pattern and evenness of light on the ground. By contrast, conventional lamp-based technologies produce light in all directions, resulting in light spilling in unwanted directions — a waste of energy as well as a form of light pollution.

Bermuda’s LED lighting is set to a colour temperature of 4,000, which puts it above the AMA threshold — but the Belco spokeswoman said that it was commensurate with the spacing of the island’s street lighting poles, which limits the intensity of roadway lighting.

“LED lights of 4,000 CT were recommended for Bermuda’s road and are being installed,” the spokeswoman said.

“Lowering the CT would not affect visibility, but would reduce clarity and ability to distinguish colours on our roads at night.”

Lowering the colour temperature to 3000 would consume more power to attain the same light intensity on the roads.

“The street lights are controlled remotely and are dimmable so lighting levels can be reduced at preset times,” she said.

“The street lights have recessed light engines and do not emit light above 90 degrees, reducing glare and light pollution.”

• Have LEDs come to your neighbourhood? Tell us if you find them easy on the eye at news@royalgazette.com.