When most people think about natural lighting what comes to mind is probably a flat-pane skylight in the ceiling, allowing light to flow directly inside. While this is one model of daylighting, it is far less common than most people think. The lighting market actually has a broad range of natural solutions, each fit to a variety of different facilities. Here are just a few of the other options for bringing sunlight into your building.
Light shelves, which are horizontal platforms placed above eye level on exterior walls to reflect light inward, provide an inexpensive but efficient way of protecting buildings from the heat gain of direct sunlight reflecting available light deep into the building. Because of the way this natural lighting is reflected and diffused, it can penetrate up to 4 times as far into a room as a traditional window—without causing glare.
Another option is exterior adjustable shades. These can be either manually operated, or automated based based on light sensors. They are one of the more aesthetically pleasing options, as they can be built from a variety of materials. These shades are extremely effective at blocking out heat gain and glare during the hottest parts of the day, however, they also block out all light, requiring more artificial lighting usage during those hours.
There are various window glazings available which can help reduce both heat transfer and glare in your building. Some are simple tinting, which has these benefits, but also reduces the light a building receives. More recently, however, low emission (or low-e) glazing has come on to the scene. Instead of simply reflecting the light away, these coatings filter out certain spectra of light, such as UV light to still provide quality natural lighting, but with minimal heat gain.
The logical progression from these specialized glazes is smart glass. This glass is coated in a material that can change its level of tinting. Some products allow this to be manipulated via a controller or smartphone app, while others adjust on their own like transition glasses lenses. This helps to keep interior temperatures stable and improves occupants visual comfort while providing consistent natural lighting.
Tubular skylights are one of the more unique natural lighting systems. They utilize a small dome to funnel light into their highly-reflective light tube. The benefit of these systems is that unlike other skylights, they don’t have to carry light straight downward into a building. These light tubes can actually be bent around ceiling level obstructions, helping to provide light in facilities that could not otherwise support skylights. The only issue with this is that each time the light is reflected, it experiences a loss of intensity. So if the light tube is long enough, the level of light that reaches the building will be noticeably diminished.
Solar Tracking Skylights
The newest development in daylighting is the solar tracking skylight. These systems utilize solar panels and GPS technology to rotate a set of mirrors, reflecting light straight downward into a building, regardless of the sun’s location in the sky. The advantage of this is that it allows them to provide light for longer hours than traditional skylights, up to 10.5+ hours as opposed to the 4-6 older systems provide. This can significantly cut both lighting and HVAC costs in a facility.