Navigant Research Blog

The Human Benefit Potential of LED Lighting

— July 1, 2016

LEDsHumans are visual creatures. Accordingly, the type of light we are exposed to can affect human behavior. Unfortunately, though, the extent to which light affects the brain is not well-known. Indeed, we understand very little about the brain overall, but the extent to which light affects the brain has until recently been largely unstudied. The emergence of LED lighting has enabled scientists to design experiments to ascertain what links exist between light and behavior. LEDs have immense controllability; they can be turned on and off rapidly (even faster than the human eye can perceive) and their color and brightness can be easily tuned. As scientific studies establish the myriad connection between light and behavior, lighting is expected to become an increasingly important part of business strategy, and not just the purview of a facilities manager.

Do You Want Fries With That?

A recent study published in the Journal of Marketing Research quantified the impact that lighting in restaurants has on what and how people eat. The researchers found that brightly lit rooms prompted diners to be more alert, increasing the likelihood of ordering healthy foods by 16%-24% over orders in dimly lit rooms. The study attributed the difference to alertness through comparison of results to follow-up studies that increased diners’ alertness through the use of a caffeine placebo or by prompting diners to be alert.

The human responses to lighting are not limited to inside buildings, either. The American Medical Association issued guidelines for communities to select LED lighting options to minimize potential harmful effects. LEDs emit more blue light than conventional lighting. Though the blue light appears white to the naked eye, it can worsen nighttime glare and decrease visual acuity. Additionally, blue-rich light adversely suppresses melatonin and can potentially lead to reduced sleep times, dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning, and obesity. The effects are not limited to humans—outdoor LED lighting can disorient some bird, insect, turtle, and fish species.

The Future Is Bright

Lighting is ubiquitous in the built environment, and as such, the potential to modify human behavior is immense. In the future LED utopia, it will be easier to wake up in the morning, eat healthily, be more productive at work, and be a better person. Beyond personal implications, lighting presents opportunities to businesses as well. Whether it is attracting top talent or increasing sales, many of the challenges businesses face may be addressed by lighting. As we better understand the impact of light on behavior, savvy businesses will be able to translate this effect into better performance.

 

New Zealand Street Lighting Updates Could Make for an Attractive Market

— May 5, 2015

New Zealand lighting designer Bryan King estimates that his country is roughly 5 years behind the United States in terms of upgrading street light infrastructure from high-pressure sodium (HPS) to light-emitting diode (LED). Recent developments and a successful Road Lighting conference, however, may help close that gap quickly or even put the small country in the lead. This makes for an interesting case study in how a smaller market can rapidly shift from one technology to another, undergoing the process at a much faster rate than larger markets are capable of doing.

Favorable Factors

According to Navigant Research’s Smart Street Lighting report, there are an estimated 370,000 street lights installed in New Zealand. This represents a small fraction of the installed base of the United States and other large countries, making the challenge of upgrading far less daunting. Another significant factor that this country has in its favor is that municipal lighting is generally owned by the municipality, rather than by a utility that may not have a financial incentive to reduce electricity consumption, especially during nighttime hours. In addition, 50% of funding for street lighting comes from the NZ Transport Agency. This government agency has recently stipulated that its funding must be spent on LED lights and not on older lamp technologies. That alone will spur retrofit projects and likely means that no new HPS luminaires will be purchased.

The recently held Road Lighting 2015 conference is also expected to drive adoption of both LED street lighting and networked street lighting control. The conference organizers were able to gather representatives from a significant portion of the country’s municipalities, who then learned from city managers and other experts from around the world who have already implemented LED and controls projects. While decision makers in the United States often seem reluctant to draw on international experiences, decision makers in New Zealand were quite eager to benefit from the lessons learned by their peers around the globe.

Road Lighting

A significant focus of the Road Lighting conference was on the use of networked controls to deliver advanced control features to street lighting systems. As discussed in Smart Street Lighting, networked systems are being adopted in ever growing numbers around the world, but many municipalities have upgraded to LEDs without also adding controls. A new and widely adopted American National Standards Institute (ANSI) standard (136.41) means that adding controls after a luminaire has been installed is relatively simple, but it still involves physically accessing every single street light. Thus, it entails a cost and effort that deters many municipalities. New Zealand is in an excellent position to take advantage of the benefits of both LEDs and controls, installing both of these now maturing technologies at the same time to reduce costs.

It is yet to be seen just how quickly New Zealand will adopt LED street lighting and networked lighting control. The City of Auckland has announced plans to switch all of its lights to LEDs in the next 5 years, and the timeline is expected to be similar for other cities and only slightly slower for smaller municipalities. So, while the total market size is modest, the rapid changeover when conditions are ripe can still make a small market attractive to international manufacturers.

 

White or Blue Debate Reveals the Science behind Sight and Lighting

— May 5, 2015

The human brain is exceptionally good at perceiving the true color of an object, regardless of the color or brightness of the light that is illuminating that object. Your mind’s eye can usually tell that the color of your scarf stays the same as you walk from a dimly lit interior room out into broad daylight—even though the actual light bouncing off that scarf and into your eye changes dramatically. That is not, however, always the case. In certain cases, the brain can be tricked into misinterpreting the light and the contextual clues that it is receiving. This was the case with the picture of a dress that recently took the Internet by storm. Viewers could not agree whether the dress was blue and black or white and gold, and the difference hinged on how each person’s brain interpreted the type of light that was shining on the dress. The best detailed explanation I have found for this phenomenon can be found at Wired.

Undesirable Byproduct

While the phenomenon of this dress is fascinating, it is a byproduct of lighting that any retail store hopes to avoid. For many years, that desire has kept retailers from using efficient fluorescent lighting; instead, they have been choosing much less efficient halogen and high-intensity discharge (HID) lighting. No shopkeeper wants a customer to purchase a sweater that looks red under fluorescent lighting, only to discover upon walking outside that it is actually orange. With the advent of LED lights, however, those stores no longer have to choose between accurate color rendering and efficiency. High-quality LEDs have color rendering indexes (CRIs) above 90, approaching the benchmark of 100 given to incandescent lights. In many ways, the light from LEDs is actually superior to that of even incandescents, allowing a lighting designer to highlight and draw out specific colors. LED manufacturers have highlighted this aspect prominently, demonstrating how sample products can look more appealing under well-designed LED lights.

Shed Some Light

Another potential benefit of LEDs in retail stores is color tuning: the ability to change the color temperature of the light produced by the LEDs from a warm yellow to a colder white or, even more dramatically, all the way from red to blue. That could allow retailers to show their customers how a handbag will look under the light of the setting sun, as well as during the glare of the midday sun or under the monochromatic light of high-pressure sodium street lights. Such a system might also be able to shed some revealing light on the Internet’s favorite dress. It would recreate the glare of natural and artificial light shining from different angles and finally allow those of us who simply can’t make our brains see anything but a white and gold dress to accept the reality that it really was blue and black.

 

LEDs Light Capital’s Streets

— April 13, 2015

There’s a certain glow to Washington, D.C. these days. It isn’t the cherry blossoms emerging after a dismal winter, or even the recent visit by Prince Charles and Duchess Camilla. It’s the street lights. In 2013, the District Department of Transportation (DDOT) announced plans to upgrade 71,000 street lights to light-emitting diode (LED) lighting. The installations finally started in March.

Each LED lamp consumes about 350 kWh less annually than the high-pressure sodium lamps they are replacing. In addition to lower energy, LEDs have a longer lamp life, which translates to lower maintenance costs. The quality of the light is also better. LEDs provide white light as opposed to the yellow light of high-pressure sodium. According to the DDOT, the white light provided by LEDs lets security cameras more accurately record color. As a result, the color of cars, clothing, or people involved in crimes caught on camera can now be better identified. Moreover, LED lighting enables more systematic and dynamic control of street lighting, as networked control systems can be added to street lights that can bring additional energy savings.

Free Lunch, Almost

Indeed, the numerous benefits of LED street lighting, coupled with the falling price of LEDs, is driving a global transition from older lamp technologies. Many cities around the world have announced similar programs to deploy LED street lights, including Los Angeles, Acapulco, and Guangdong. According to Navigant Research’s report, Smart Street Lighting, LED luminaires are expected to rapidly surpass high-pressure sodium luminaires as the leading technology sold.

So what should Washington, D.C. do with all of these savings? The city council has a long history of finding innovative new ways of spending surplus money (or not). Annual energy savings of about $40 per light for roughly 70,000 lights translates to $2.8 million — not bad for a city of 658,893. That’s enough to buy every resident a rush-hour trip on the metro from RFK Stadium to Friendship Heights. Unfortunately, it’s not quite enough for a chili dog at Ben’s Chili Bowl. Alternatively, spending the entire $2.8 million on a single item sounds fun. The Pagani Zonda Revolucion comes to mind.

 

Blog Articles

Most Recent

By Date

Tags

Clean Transportation, Electric Vehicles, Finance & Investing, Policy & Regulation, Renewable Energy, Smart Energy Practice, Smart Energy Program, Smart Transportation Program, Transportation Efficiencies, Utility Innovations

By Author


{"userID":"","pageName":"Energy Efficient Lighting","path":"\/tag\/energy-efficient-lighting","date":"7\/24\/2016"}