led streetlights in chicago

How Smart are the New Smart Lights?


HOW SMART IS CHICAGO’S NEW SMART LIGHTING PROJECT OR—Can someone please turn out the light, already! We’re trying to get some sleep.

For a while there, the world couldn’t stop getting brighter. I’ll call this time the 80s, where the digital watch went from pricey noveau electronic to novelty item that popped up on every wrist. Big and bulky—making its sleek analog golden-bangled counterpart shiver in its grave, the digital watch exploded in popularity because…wait…why did it do that again? The average American spends over 8 hours a day staring at smart screens, emitting blue light which is known to disrupt circadian rhythms. Smart lights, the more energy efficient and brighter answer to street lights, are popping up all over the U.S., basically adding another source of eye strain for the population at large. 

It is not only appliances and technology that have gotten the ‘screen facelift’ unnecessarily. Menus which switch from listing prices and items (helpful information) to displaying up close photos of fake fast food meant to elicit appetites make me cringe. What a waste of electricity! What pollution to the ambient environment! Gas stations and convenient stores now advertise their wares with glowing white slideshows. And all the while the sleep of the average person is growing more fraught by the year. Not to mention those poor rabbits and birds which call the outdoors their bedroom. In my room alone I count four gadgets beeping and blinking, not to speak of the world outside my window, where the night sky is no longer velvety dark but glowing and buzzing faintly as far as the (rapidly decaying) human eye can see. For as many years as I can remember the streets lights were out there, fair weathered friends which helped me feel safe as I wandered home on my quiet, non-bustling streets, but which also prevented me from fully relaxing or appreciating the full spill of stars over the midwestern sky.

On April 17, Mayor Emanuel announced that in conjunction with CDOT, Chicago would begin the process of overhauling 270,000 of its streetlights (approx. 85%) and replacing them with LED smart lights. But how smart are these smart lights? They are certainly one helluva lot brighter. Like, shooting star bright. But is brighter always better?

First, let’s start with the benefits.

New Smart Light Acorn Fixture

New smart light on Bosworth, casting a pretty strong glow. Photo credit: moss


LED lights are commonly known to consume drastically less amounts of electricity, and these new lights are no slouch, slashing energy consumption by 50-75% for the new smart lights. LEDs achieve this by releasing far less of their energy as heat than incandescent or CFL bulbs, which release 80 percent+ of their energy in the form of heat. LEDS can also be honed in a particular direction, resulting in sharper focus, reduced need for dependency on diffusers and reflectors, and an overall brighter light. (source: energy.gov). What with the city’s debt and all, it couldn’t hurt to rake in the savings. And, Emanuel assures, these lights will not result in an increase in taxes, as the savings accrued will be reinvested into the modernization process. (source: City of Chicago Press Release, April 17, 2016)

In his press release, Emanuel calls the current street light technology, High Pressure Sodium (or HPS) lamps inefficient and outdated. When it comes to the visibility of color, he is certainly correct. Ever wonder why the old HSP’s give everything that warm orange glow? Powered by LED, the new smart lights can produce pure white light, from the mixture of red, green and blue wavelengths which combine to cover the full light spectrum when shined on an object. HSPs, by contrast only cast yellow light, covering a narrow slice of available wavelengths. When HSP light is shone on an object, it will either absorb this yellow-orange light, or reflect it, resulting in a monochromatic scale of greys, blacks and various shades of yellow. In the real world, this means if you’re in a parking lot after dark or walking home alone, the new street lights can help you can verify that that red Toyota Corolla is in fact red, and therefore yours, or that the cat scampering away in the distance is your persian blue. Maintaining full visibility (or at least closer to it) could help identify the clothing or car of a perpetrator in hit-and-run crimes or other assaults, making this a safety feature that would be welcome in large cities like Chicago.

High Pressure Sodium lights

LED Streetlight

Comparison of the old lights (top) and new lights (bottom). Both taken at same exposure (5″) and f stop (f/18). Photo credits: moss


Currently, the city relies on resident reporting (that means you!) calling them to let them know the street lights are out. From the City’s Press Release: “CDOT receives more than 100 calls each day to report lighting outages,” CDOT Commissioner Rebekah Scheinfeld said. ‘The new Smart Light management system that will be part of the Chicago Smart Lighting Project will greatly improve the efficiency of city forces and allow us to respond proactively when outages do occur and restore service more quickly.” With new smart lights, a network of lights are able to communicate to a hub, reporting power outages instantaneously, and resolving these issues quicker as a result. Possible, though as of yet unconfirmed features of smart lights in general include security monitoring, gathering data for first responders, recording and transmitting traffic data, and even reading utility meters or providing wi-fi. Smart lights may even answer your questions about the weather in a robot voice. The possibilities are many.

Ok now, onto the negative consequences of these new Smart lights, and why we don’t think they are a great idea, despite the slew of benefits listed above.

One would think that lighting up the street more would result in more safety, just as more traffic control would result in less accidents. But this is not always the case. To wit, John Staddon’s dressing down of the four way stop as safety measure. Some studies suggest that losing the cover of night makes victims easier to target—after all, we’re not the only ones who can see better in brighter lighting. And also, who’s to say that we’re seeing better—Darksky.org cites a 2012 AMA report which states that glare from bright unshielded lights can shine too directly into eyes, constricting pupils, which actually decreases visibility, and makes it more difficult to adjust to lower lighting conditions. A nice, dim, warm glow would do for de-spooking neighborhoods and public spaces, promoting gathering and socializing and increasing the sense of safety residents feel when out and about. Though the connection may be tenuous, one thing’s for sure, if a crime is already in progress, pitch black environs aren’t helping anyone, so we would never advocate for a removal of the street light systems in total. 

LEDS are lovely in that you can dim them to a variety of brightness levels and color temperatures. Since the brain is programmed to interpret blue light as wakefulness and orangey-warm-glowy lights as restfulness, wouldn’t it make sense to take advantage of the versatility of LEDs and have them cast a delicate, more candlelight-style glow, instead of a blindingly bright light that disintegrates melatonin in its tracks?

Smart Light shining on Building

The new lights really light up residential blocks. Photo credit: moss


The new smart light design, an acorn style lamp on a long arcing arm (pictured), casts a bright halo up and out into the night sky—and right into you and your neighbor’s windows. There is no shortage of studies which document how real the connection is between disrupted sleep and exposure to artificial light during sleep hours. Melatonin, the chemical which makes it hard to keep your lids lifted is produced chiefly in the pineal gland, an endocrine powerhouse which, nonetheless halts melatonin production when any number of disruptors—from nicotine, to caffeine, to the 2016 Election—send it messages that it is no longer time to rest. Blue light, like that glow from your computer, smartphone, or TV is right up there with a jolt of java in preventing you from catching your Zzzs. More than any other kind of light, it suppresses melatonin production and causes an upswing in attention and reaction time. So while LED lights are much more efficient and will certainly save you on your electric bill, they may cost you in quality, deep sleep which has restorative benefits that affect every single aspect of your quality of life. It is this type of definitive research which makes the canned answer to the questions about sleep quality and light pollution all the more frustrating in regard to the Smart Lighting Project (see page 1-2). The HSP lights were at least warm-toned orange, reminiscent of fires which humans have been sleeping around since the dawn of time (ish). It has also been proven that red light has the least power to disrupt circadian rhythms. These newer smart lights are sure to not only disrupt people who sleep without blackout curtains stapled around their window, but people who are on their way home, as it is recommended to remove exposure to blue light 30-60 minutes before bedtime to achieve a deep sleep.

Light pollution is an unavoidable affect of an industrialized society, especially densely packed cities with 24-hour nightlife, expensive jewels sequestered in marble museums and all other manner of lighting scattered throughout. But what do we lose when we leave our lights on all night? We lose the stars. We lose many forms of wildlife. And we confuse and derail birds. Birds use the moon and the stars to help them orient as they migrate, and they, like us, and most other animals need to regulate melatonin through exposure to light. If the lights are always on, they are becoming stressed, unhealthy and at risk. We can’t afford another silent spring, or even semi-silent one. Stargazing connects us to the past, future and all that we haven’t explored yet. Too-bright street lights that make us cranky and sleep-deprived aren’t worth obscuring it in a yellowy haze. The shield on the new smart lights is an acorn style shield, reminiscent of when cobblestone streets reflected gas lamps onto horse hooves. But using them for a modern light which dwarfs the humble glow of the gaslamp seems ill-conceived. In our last post on light pollution we explored the benefits of directing light at the ground, minimizing glare and using light most efficiently. Shielding lights helps keep them directed and efficient, so we think there should be a more substantial shield for a much brighter light. Considering that these new lights are spaced much more frequently, the negative consequences of light pollution, glare and sleep disruption will likely be amplified. 

In conclusion, we appreciate the effort being made to modernize our streetlights with the new smart lights; we believe its heart is in the right place. But we firmly object to these super bright lights unadultered, which almost project daylight-like conditions in the dark of night, adding to the light pollution in the sky, further obfuscating the stars, and disrupting our precious sleep.