Daylight Harvesting Brightens The Day, And The Bottom Line

By Pete Shannin

The payback value of daylight harvesting, leveraging skylights in conjunction with LED luminaires and lighting controls—reducing electric light load when skylights can make up the difference—can typically reduce electric lighting costs by a staggering 80% in retail, workplace and educational facilities.daylight harvesting

Along with energy savings, studies show the human benefits of daylighting for building occupants are similarly enlightening: reduced absenteeism, improved overall well-being, and improved productivity. This is because daylighting takes smart control of natural and electric light without disrupting the user’s environment and provides better full-spectrum light—that is 100% diffused, glare-free, and produces no flicker.

Take education and retail as examples. A study initiated by the Pacific Gas and Electric Company (PGE) showed that students with the most daylighting in their classrooms progressed 20% faster on math tests and 26% faster on reading tests in one year than those with the least. Teachers and administrators enjoy such high performance, plus the results of reduced energy costs, less maintenance, better visibility, and increased flexibility of how lighting is used in the classroom, gym and other spaces. In the retail space, daylighting increased sales by 40% in stores with skylights when compared to identical stores without skylights in the same study. Clearly, merchants can rely on utilizing natural daylight to support merchandise displays and provide a better in-store experience for their customers.

Daylighting For Financial And Employee Benefits

A manufacturing company obtained financial and employee benefits through better lighting when it built a warehouse with daylighting as an integral part of its design. As featured in a recent Eneref daylighting advocacy report, Karndean DesignFlooring, a vinyl tile manufacturer in Pittsburgh, PA, embraced daylighting to cut energy costs and enhance employee satisfaction. The design team installed Sunoptics Signature series prismatic skylights along with Lithonia Lighting IBL LED high bay luminaires and Acuity Controls.

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At its Pittsburgh, PA warehouse, Karndean DesignFlooring maximizes natural daylight into the interior. Sunlight triggers sensors to reduce or increase electric light output.

Karndean’s holistic design approach to daylighting reaps the maximum benefits from natural light and energy savings. LEDs require less energy than the previous T8 fluorescent lights. Meanwhile, Karndean’s new lighting system maximizes natural interior daylight via sensors that further reduce energy use by automatically dimming the LEDs based on the amount of daylight available. And LED high bay fixtures include integrated controls and photo dimming sensors to not only reduce energy costs, but also help extend the life of lighting fixtures.

Karndean employees attest that installing this lighting system significantly improves their work environment and their ability to serve their customers. Chris Wettling, warehouse manager, comment, “With the skylights mixed in with the new LED lights, it certainly makes a large difference for us, from that ability to see if there are any variances, not only in color but also in the sheen and texture of the flooring we are shipping out.” Karndean employees also confirmed that the subtle brightening or dimming of the LEDs is barely noticeable as the sunlight triggers the sensors to reduce or increase electric light output.

An Integrated Solution for Uniform Color in Common Spaces

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Daylight harvesting at Karndean DesignFlooring warehouse facility.

Lighting technology continues to improve for heightened quality and aesthetics. Integrated lighting solutions can provide uniform color in common spaces such as offices, retail environments, and education facilities. However, the ability to provide such a proposition using daylighting has been limited until now.

As an example, Sunoptics Prismatic Skylights, recently launched the new LightFlex™ CCT concept, allowing architects and lighting designers to maintain consistency in their color specification while taking advantage of the benefits of natural daylight. The LightFlex CCT is a tubular prismatic daylighting solution for suspended ceiling applications. It uses a patented remote phosphor panel to integrate seamlessly with electric light fixtures in shared environments. The system achieves color temperatures similar to those used in commercial lighting systems by minimizing the color temperature variation between the electric and natural light sources.

Daylighting technology like this helps facility executives and their architects and designers meet compliance with building codes, which are more stringent in performance requirements for skylights and controls on electric lighting. Prismatic skylights can help projects achieve LEED v4 points and meet building energy codes and standards such as ASHRAE Standard 90.1, IECC and IgCC.

Savvy business owners and commercial space managers understand the many benefits of daylighting and how taking advantage of natural light will provide better environments for people to work, shop, and learn. Those who benefit from daylighting’s energy savings also enjoy the positive end results of reducing greenhouse gases and pollution. The application for daylighting—warehouse, manufacturing facility, big-box retail, school, office space—is not as important as the end result: the improvement of light and life inside.

daylighting harvestingShannin is the vice president of Daylighting Product Solutions at Acuity Brands Lighting. He is responsible for leading all aspects for product development and marketing of holistic daylighting solutions featuring prismatic skylights, LED lighting, and lighting controls. Prior to this role, Pete led the commercialization start-up of the Acuity OLED lighting business, as well as leading corporate development efforts for multiple acquisitions.