Daylight Harvesting is one of the most exciting and innovative fields in sustainable lighting design for buildings. If you’re not familiar with the term and are interested in saving energy in your business, then it would benefit you to get acquainted and start incorporating daylight harvesting into your lighting system in whatever ways you can.
The simplest definition of daylight harvesting is this: It’s a method to collect natural daylight in the interior of buildings wherever it’s available, thus reducing the need to operate artificial electrical lighting. Though daylight harvesting can be effective in any building, given it has windows, skylights, etc., green buildings are being specifically designed to gather and distribute the daylight available in more areas of the building, utilizing electrical lighting only when needed.
Daylight harvesting techniques help buildings draw more natural light into their interiors at more times of the day, thus reducing even more need for artificial lighting. This is accomplished through the use of skylights, windows, and other implements like light pipes that increase the distribution of the natural light in the indoor spaces. This natural light is then supplemented by using sensor-controlled LED lights that adjust the amount of artificial lighting used based on how much natural light is available. Using this technique, the tenants of these buildings can always have their lighting at appropriate levels for work or any other activity while also saving energy.
The Evolution of Daylight Harvesting
As a practice, daylight harvesting has evolved extensively over the last few decades, transforming from an afterthought in buildings to an exciting component of sustainability that is being implemented more and more into green building design. The reasons for this are strong. Any new building project implementing daylight harvesting ideas into its construction is setting up its tenants for success, allowing them to save even more energy on lighting than they would by just switching to energy-efficient LEDs or sensor lights.
Another reason to incorporate daylight harvesting into a space is the effect of sunlight on the wellbeing of building occupants. Sunlight has been shown to be healthier and more psychologically beneficial than artificial electric lights.
Natural sunlight does this by maintaining the circadian rhythms that are crucial to good health and adequate sleep, and help to prevent seasonal affective disorder, or SAD, which is often linked to being exposed to lower amounts of natural light. Using these daylighting techniques, many offices and other commercial spaces have seen more productive employees and higher consumer sales. Couple these benefits with the energy you’ll save by incorporating daylight harvesting into your lighting system, and it truly is a win-win for everyone.
How Daylight Harvesting Works
There are many steps to implementing effective daylight harvesting in a building. The beginning step, if the project is a new building, is to design the space so that it gathers more light during daytime hours. This can be accomplished with building orientation toward the sun, allowing the various indoor spaces to gather appropriate amounts of sunlight at certain times of the year. By placing windows, skylights, and other implements like light wells in the building, diffused light can illuminate more spaces inside the building. Paired with LED lights, you can maximize lighting efficiency in your building.
The next step is utilizing sensor lights that can measure the amount of light in any given room. These sensors can be mounted on walls, ceilings, or fixtures, allowing your lighting system to adjust the artificial lighting source based on the amount of sunlight currently available. That way, you can have a consistent amount of lighting in your spaces while also saving as much energy as possible based on the amount of daylight available.
One problem with daylight harvesting is the harshness of direct sunlight. Though you want to use the light of the sun, you also don’t want direct sunlight falling on any people inside the building. As we all know, direct sunlight can be very intense, not to mention the health risks associated with too much sun exposure. The goal, then, is to use the daylight effectively inside the building but also diffuse it so that the end result is a gentle, balanced light inside every space. Aiding this with energy-efficient LED lights and sensors means you’ll always have the light you need.
There are a few concerns with the practice, though. Daylight harvesting is much more effective in sunnier cities where you can consistently rely on daylight hitting your building. Also, the heat of the sunlight is a factor, especially during summer months when you’re running the air conditioning to combat hot, sweltering days. By using special glass that will reduce the amount of heat coming through windows and installing shades that will automatically adjust to sunlight, you can still effectively use daylight while also experiencing minimal solar heat gain in the building’s interior.
Other factors like glare and light obstructions can also be worked around with the right techniques, leaving you only with the energy-saving and uplifting benefits of daylight harvesting in your space.
Why You Should Utilize Daylight Harvesting
The number one reason for utilizing daylight harvest is energy savings. The cost of implementing daylight harvesting into your building will be offset very quickly by the energy savings you’ll experience on every bill. After the cost is offset you’ll experience a positive return that will only increase with time.
Also, you can’t deny the benefit of increasing the amount of daylight in the building. The psychological benefits of exposing tenants, employees, and other building occupants to natural light are hard to put a number on, though its positive impact will be obvious before too long. Happy workers and tenants make a more productive space for everyone.
Shine Retrofits offers many sensors and lights that are optimal to install in a daylight harvesting system. Browse through our troffer fixtures, then check out our comprehensive list of lighting controls and sensors, which include daylight harvesting products and other sensors like occupancy and vacancy sensors.
Shine Retrofits wants to help you implement daylight harvesting into your spaces. Our work in energy efficient lighting systems has driven us to be an integral part of this burgeoning field. Feel free to contact us with any questions—we’re excited to help you experience the benefits of sunlight.