The 2,700-year-old city of Rome is one of those places where public lighting really does mean everything.

Famous for radiating with a gentle golden glow after dark, visitors to Rome have come to expect the Eternal City to be filled with romance, intrigue, hideous traffic and streetlights that evoke an intimate, candlelit dinner of spaghetti cacio e pep and not a Saturday afternoon trip to the DMV.

So it’s understandable that some Romans might feel angered and perhaps betrayed by the city’s 48 million-euro scheme to replace the city’s signature yellow sodium-vapor streetlights with LED lamps, which use less energy while helping to better illuminate dodgier pockets of the historic city center. As reported by the New York Times, there's no argument that energy conservation and public safety are two noble and needed issues for the city to tackle. But judging by the reaction of some Romans, you’d think they dyed the water of the Trevi Fountain the same unnatural shade of blue found at mini-golf courses.

“Illumination is atmosphere. They are assassins of the beauty of Rome, of its history,” municipal council member Nathalie Naim tells the Times in reference to the decision makers at City Hall. “I don’t want to make this personal, but these horrible lights, mamma mia!”

Struggling to get an official response from officials involved with the sodium bulb swap-out initiative but buoyed by backing on social media, Naim has been a vocal critic of city hall and the municipal electricity company, which has been tasked with replacing the beloved old lamps with LEDs. Critics such as Naim claim that the retrofitted lamps are polluting Rome’s cozy, ancient streetscapes with a ghastly white light. (Rome, as it turns out, has a complicated relationship with light pollution — the dimmer, the better it would seem in the Eternal City.)

To date, roughly 100,000 bulbs have been swapped out, the half the total number of bulbs that the city plans to retire and replace with LEDs. City officials — including Mayor Virginia Raggi, who is leading the push for energy conservation — expect to save millions in energy expenditures when all is said and done.

A streetlight in Rome Although they don't do wonders for efficiency, old sodium streetlights lend Rome a hazy allure that's difficult (but not impossible) to replicate with LEDs. (Photo: Vassil Tzvetanov/flickr)

A matter of 'aesthetic coherence'

In addition to actually quoting a native Italian saying "mamma mia," the Times lays it on pretty thick when describing the drama surrounding Rome's re-lighting:

At the very least, it has not pleased all the residents of the Eternal City, who are apt to eternally complain. They say they have suffered enough indignity, decay and decline in recent years because of corruption and lack of services. Now, when they are finally presented with a change to try to improve the city, they find it is no improvement at all.

But not to despair. Advances in LED technology have yielded warmer-colored options (less blue wavelengths, lower color temperature) that don’t necessarily cast the offensive white glare associated with early energy-efficient lighting. (And from photos published by the Times, the difference between the orange-ish Old World glow of the old streetlights and the almost blinding whiteness of the new streetlights is quite dramatic.) Yet in what appears to be an oversight with regard to aesthetics, officials in Rome have gone ahead and opted to go what appears to be the more harsh route.

The Times notes a few rather ghoulish comparisons associated with the new LEDs such as “morgue,” “hospital” and “cemetery” have been mentioned by the public. By my eye, the streets of Rome depicted in the Times photographs appear to be lit up like a nighttime Little League game — which isn't necessarily a bad thing except for the fact that a sweeping, monument-studded Roman piazza isn't a Little League Field.

When reached for comment, an unidentified spokesperson with Roman electric utility ACEA defended the decision, noting that some parts of the city were too moodily lit and that the brighter lights would help to deter crime and promote public safety. He also notes that, in consultation with Rome’s cultural authorities, streetlights in the city’s more touristy historic quarters would continue to emit a more seductive, eye-pleasing tone.

After noting the myriad environmental and economical benefits of swapping out old-style public lighting with more efficient LEDS, Roberto Zamboni, an illumination expert with the Italian National Research Council questions: “But are we sure we want to put them in historic centers without taking into account aesthetic coherence? Perhaps this is an issue for architects, because there are solutions.”

And then there are the Romans who just can’t be bothered by rows over urban lighting. “It’s how you live the city, not the lighting, that makes it romantic,” salon manager Cosimo Barnaba tells the Times. “Rome is always beautiful, even with a white light.”

Piazza Navona, Rome At night, Rome's famed public spaces like Piazza Navona are illuminated by a romantic golden hue provided by aging, inefficient lighting technology. (Photo: Luigi Guarino/flickr)

Blue wavelengths and even bluer moods

While Rome might be one of the oldest cities across the globe to invest in a LED streetlamp conversion, it's far from the first.

Just this week, Chicago selected a vendor to head its multi-year, $160 million streetlight replacement project. Starting in with neighborhoods that have “heightened security concerns,” a total of 270,000 Chicago will be replaced with the new bulbs consuming 50 to 75 percent less electricity than the current sodium streetlights. The spokesman with ACEA even admits that Los Angeles, a city that’s LED Replacement Program has reduced public lighting-related energy usage by over 63 percent while lowering carbon emissions by 47,583 metric tons annually, inspired Rome to take action. (Geoff Manaugh’s 2014 article for Gizmodo on how the LED-ificiation of L.A. is impacting the city’s film industry is a must-read).

As of 2015 Paris, another European capital city famous for its dimly lit ambiance (not to mention its lights), continues to stick with less efficient high-pressure sodium bulbs. However, the city has also adapted a smart wireless networking system that remotely controls and monitors the city's public lighting grid, streetlights and traffic lights included. (Normally, such systems are paired with LED lighting.) Paris eventually plans to convert to 85 percent LED by 2020. "They didn't want to disrupt the colour of the city of Paris — but the new controls alone gave them a 30 percent energy saving," Brian McGuigan of Silver Spring Networks, the Silicon Valley smart grid provider that created Paris' system, told the BBC this past October.

In the meantime, the streetlights of Paris, Tennessee, are going full LED.

In other cities that have ditched high-pressure sodium lamps in favor of older model LEDs, reaction has been similarly mixed with much of the criticism focused on potential health fallouts than ambiance-ruining as is the case with Rome. As my colleague Starre Vartan previously reported, the potential ill effects — scorched retinas and out-of-whack circadian rhythms, included — of LED street lighting were put in an appropriately glaring spotlight this past fall in a report published by the American Medical Association.

Reads the AMA report: “Many early designs of white LED lighting generated a color spectrum with excessive blue wavelength. This feature further contributes to disability glare, i.e. visual impairment due to stray light, as blue wavelengths are associated with more scattering in the human eye, and sufficiently intense blue spectrum damages retinas. The excessive blue spectrum also is environmentally disruptive for many nocturnal species.”

As mentioned, LED lighting has evolved to be not-so-white and not-so-bright while maintaining the same public safety-boosting, money-saving, CO2-reducing benefits that city governments and urban planners initially found so attractive. Furthermore, the public health concerns associated with LED streetlights are largely avoidable with the proper foresight and smart design.

Still, for some, LEDs will never be able to replace murky yellow hue produced by antiquated sodium lamps in places like Rome and Paris where mood lighting doesn't just provide illumination but the city's identifying character. It's better, but not quite the same.

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.