LEDs: How human-centered lighting design improves urban life
Light is like interface design, when it’s done well it’s invisible but has a significant positive effect on a person’s experience and interaction with a space or object.
What are LEDs?
Light-emitting diodes (LEDs) currently represent what is perhaps the single most important trend in lighting for both residential and commercial installments of light. In 2019, almost half of all light sources globally were LEDs and it is projected that by 2030 nearly 87% of all synthetic light on the planet will be emitted by LEDs.
By 2030 nearly 87% of all synthetic light on the planet will be emitted by LEDs.
Terry McGowan, head of the American Lighting Association refers to the advent of LEDs as the fourth age of electric light evolving from a continuum of incandescence, fluorescence, and high-intensity discharge (HID).
With a lifespan that is 25 times longer than traditional incandescent bulbs, and up to 90% more efficient, LEDs are small in size, incredibly versatile, and convert nearly 100 percent of the energy they consume as light. According to the U.S. Department of Energy, the widespread installation of LEDs can save 348 TWh of energy by the year 2027, enough energy to power 44 electric power plants and save more than $30 billion dollars.
LEDs are some of the most efficient lighting solutions available today and designs are only growing more versatile and affordable.
What is Human-Centered Lighting design?
Similar to the field of human-centered design, there are human-centered lighting principles. Human-centric lighting (HCL) is the art of creating lighting that mimics the natural daylight which drives our bodily functions. It enhances human performance, comfort, health, and well-being.
The most obvious effect of light on humans is vision. It enables us to identify brightness, shapes, colors, and images, and perceive information and contrast. But light also affects us emotionally and HCL considers how mood can be improved to influence productivity, happiness, and relaxation. Light impacts human biology with effects on hormones, alertness, attention, and fatigue, and also determines the natural circadian rhythm of the body.
Human-centric lighting takes these effects into consideration to provide a holistic and application-oriented approach to lighting and balances these needs in lighting applications.
For example, Color tuning adjusts the light temperature and color pumping allows for a boosted output of a certain spectrum of light. These processes create advancements like “true color” allowing the eye to perceive objects in their natural color. Philips points to applications for this technology like enhancing the presentation of colors when your dinner hits the plate or when choosing an outfit.
Applications for HCL
Improve sleep and mood
The common conception of the impacts of LED light tuning is that blue light stimulates the brain and amber helps it to relax. Thus, designers are tending to specify systems that deliver those frequencies at the desired time of day or in the desired setting.
The body’s natural clock is referred to as the Circadian Rhythm which is responsible for regulating feelings of sleepiness and wakefulness. The effects of our lifestyles have led to a reduction in general restfulness making sleep and restfulness more elusive. Hacking sleep is among the newest biohacking crazes and numerous sleep technologies have been designed to help us get back to sleep. In 2019, the global sleep economy was valued at about 432 billion U.S. dollars; it is forecast to be worth 585 billion U.S. dollars by 2024.
Here’s how LEDs fit in…
There is a strong connection between human sleep cycles and lighting temperature. Color tuning advancements in LED allow users to adjust (or automatically adjust) lighting in objects or bulbs based on the time of day. This lighting can be tuned to a color temperature similar to natural sunlight encouraging productivity or alertness when it’s time to work, and later the same lights can be lowered to a warmer color temperature for better sleep. In other tech objects like phones or computers, light tuning can be adjusted to reduce the blue light output and prevent prolonged stimulation.
Enhancing productivity and alertness
The invention of artificial light revolutionized society. It brought people indoors and extended working hours, nightlife, and education far beyond sunset. Studies show that in our current lifestyles we are exposed to less light than is sufficient to trigger a positive circadian rhythm. Spending so much time indoors reduces our exposure to natural light which is proven to have an impact on cognition, alertness, and well-being. However, we don’t yet have a full, evidence-based understanding, of how the full spectral power distribution of light can really impact human performance.
What we do know is that in commercial workplaces, the effects of appropriate lighting correlated with color temperature can make the office environment feel more natural and comfortable while improving productivity and retention. Similarly, schools using HCL practices can help to both calm students and keep them alert depending on the time of day.
Health care settings
By controlling both the intensity and the color of the light, lighting design can provide an additional improvement in occupant satisfaction and productivity. Healthcare facilities are using HCL to adjust for cooler color temperature light in staff areas keeping employees more alert during shifts, and in patient rooms, color temperatures are warmer to keep patients comfortable and relaxed as they rest and recover.
In children’s hospitals, iPads that control the colors of the light in wall panels can make young patients more comfortable and provide a helpful distraction.
Typically, night lighting is a safety requirement for hospitals, needed for way-finding and around-the-clock care. Patients, however, will sleep better in near-complete darkness. Balancing these priorities can be done by using warmer light temperatures in hallways to reduce the harmful white or blue light effects and provide more restful sleep.
Connected lighting and data
In the cities of the future, energy-efficient LED street lighting enhances safety and visibility at night, a network that provides optimal infrastructure for streaming data between connected devices and assisting in smart vehicle wayfinding. LED lighting fixtures can transmit wireless data at very competitive high speeds. This new network will make internet access plentiful and nearly limitless and will be accessible as off-the-shelf LEDs.
Vertical indoor farming
When LEDs are used in urban vertical farming, you eliminate the need for pesticides and fertilizers and reduce food mileage.
LEDs are ideal for propagating young plants, cultivating leafy greens, herbs, and fruits, and developing new varieties of seeds. The use of LEDs in this application can encourage higher yields on a smaller footprint making verticle and urban farming more easily attainable. There is also an opportunity to steer unique properties in crops, like enhanced flavor, nutritional value, and shelf life. LED use has been shown to improve nitrate concentrations and vitamin C content in produce.
Farms can control the timing and duration of light hours per day, create uniformity across crops and consistent growth, take advantage of light spectrums for consistency and efficiency and change the amount of light.
Safety lighting
Solar LED lights come with rechargeable batteries and are powered by photovoltaic panels. These photovoltaic panels help in charging the batteries in the daytime, and then they power the LED lamps to provide optimum light at night. Too much lighting can also cause problems, but with LEDs, the lights can be customized to decrease the risk of accidents.
Solar LEDs are cost-effective and are designed to turn on and off automatically according to the lighting conditions. Their small size and flexible application mean they can be integrated into crosswalks, road surfaces, walls, and sidewalks to enhance nighttime visibility leading to fewer accidents and enhanced safety. For example, sensors can be programmed to scan roads for pedestrians or cyclists and transmit the data to autonomous vehicles preventing collisions.
Extending public spaces
Public spaces are essential to modern urban life, especially as we spend more time indoors for work and relaxation. For urban spaces to be perceived as welcoming and safe, they must be sufficiently well-lit.
Effective lighting of parks and public spaces combine engineering solutions with urban strategies. LED lighting can make spaces more inviting and help create a visual experience. Lighting can do a lot to alleviate the fear of crime, and therefore encourage greater use of these spaces, making them truly open for all. LEDs can be used to complement wayfinding and signage strategies, as public art installations, safety touchpoints, or to highlight cultural landmarks.
The scheduling of LED public lighting can provide up to 70% cost savings. Remote cloud-based management lowers maintenance costs, reduces operating expenses, and can be coordinated with street lighting with combined scheduling and system updates.
Art and architecture
Bringing public spaces to life can be accomplished through dynamic light installations, light shows and special events, and architectural lighting. The play of light across a surface like water can be replicated through lighting creating artistic and emotive displays in urban settings. Similarly, architecture installations that use light as a medium take advantage of a burgeoning dimension of interaction and experience.
Art existing outside of gallery spaces must draw on the intricacies of urban settings to promote total sensory impressions. Light, and especially that of long-lasting and versatile LEDs, provide the optimal interplay of material and ephemeral. Pedestrians of these installations have the unique ability to walk through the art, a truly immersive experience.
Predictive wellbeing
In the smart homes of the future, LEDs can offer predictive wellbeing by learning your routines and anticipating your needs.
Even now LEDs are being integrated with music streaming and gaining the ability to communicate alerts and data. In the near future, wireless internet will be streamed through LEDs and sensors will be able to recognize and set the mood with lighting and music. Just imagine a dinner party perfectly accompanied by your home's lighting intelligence.
In tune with your body's natural Circadian rhythm, lighting will automatically adjust to sleeping and waking cycles. Seasonal Affective Disorder will be combated by higher amounts of blue light on shorter days. Your lighting experience will be truly personalized to the needs of you and your family for overall better quality of life.
What’s the catch?
With their higher efficiency, LEDs are much brighter and glary than traditional sources. This makes their application to city streets a potentially complicated safety and nighttime disruption issue. Glare can cause accidents on rainy or foggy streets while an increase in light pollution can lead to sleep problems for urban high-rise dwellers.
LEDs currently have a higher upfront cost than traditional incandescent bulbs however, they become more economical over time. Just like solar pannels though, the costs have greatly reduced and will likely continue to exponentially reduce over time making the long-term investment in LEDs and their numerous possible applications the true future of urban lighting.
