What is Daylighting and Why is it needed?

Although sunlight is available for free and makes for a great source for indoor lighting, there is still heavy reliance on artificial lighting for illuminance. This is especially the case for businesses that house a large workforce. However with the increasing awareness of greenhouse effects on environment and the concerns related to energy consumption and the effect of natural lighting on health, there are more businesses looking to natural light for indoor lighting.

What Is Daylighting?

Daylighting is a way to ensure that indoor lighting is as per the required amount needed for human conditions. The way this is done is using harvesting natural sunlight using fenestrations for indoor illuminance and based on the lighting conditions indoors, automate the use of artificial lighting to compensate for dim light.

How To Implement Daylighting?

If you are constructing a new building make sure the building is oriented towards the sun for optimum radiation which has an impact on heating and cooling costs. Experiment with different daylight modeling techniques to get the right amount of internal lighting.

Simple fenestrations like windows, louvers, blinders and others can be used to control the amount of light entering the indoors of a building. One can use advanced daylighting systems like skylights and solar tubes based on the requirements.

Daylight harvesting needs to be implemented carefully so as not to create too much heat(which can raise air conditioning costs) and glare which can be very unpleasant for the occupants. The most effective way to implement the daylighting systems are with the right combination of natural and artificial light.

In most cases, the more you can automate the lighting system, the more energy you will save. For this reason, the most advanced systems are all connected to a control panel, which uses software to let you fine tune the lighting setup in every room or zone of the building. Still, it’s always a good idea to have manual overrides on dimmers and the like, so people can adjust the light to their personal preferences.

This is made possible by automating the lighting systems with control panels with software that adjust the lighting based on the internal lighting conditions. This could be manually overridden to provide the lighting as per the people’s preference.

Daylighting Strategies

Two of the commonly used daylighting strategies are:

• Top Daylighting – Daylighting systems is installed on the roof to enable lighting entry from the ceiling. These could include systems like skylights and others
• Side Daylighting – This technique allows daylight to come from the side of the building with vertical glazing on building perimeter walls.

Types Of Daylight Devices For Daylight Harvesting

Some of the commonly used daylight devices used are:

• Dimmers, Sensors and timers – These are devices that are used to control the lighting, by detecting the ambient light and automating the lighting conditions with artificial lighting.
• Shades, shutters, louvers, and other diffusers – Place these on windows and skylights to adjust the amount of sunlight.
• Skylights – Skylights are encased windows that are installed on the roofs of the buildings to allow natural light to come in. These are different types of skylights like the fixed encased windows, the openable skylights and so on
• Solar Tubes – Solar tubes are tubes that capture sunlight from the rooftops and pipe them to the indoors of the buildings. The piping of the light is made possible because of the metallic reflections that happen all the way along the tube when the light passes through it. And the finally diffused light comes out of the pipe to illuminate the indoors after passing through the diffuser.

Solar tubes are gaining popularity over Skylights because they are easy to install and are much less expensive and optimized to control light and heat indoors.

Know more about Solar tubes and Skylights.

Benefits of Daylight harvesting

The 2 major benefits of daylight harvesting are:

Energy efficiency: A lot of energy is wasted and costs for the business increases with inefficient systems. Energy costs accumulate for businesses with 3 main costs –

• HVAC costs – HVAC refers to Heating, ventilation and air conditioning costs.These are the costs that come along with the air conditioning of the buildings due to build up a lot of heat and much of the energy goes into cooling down these systems. These costs can be saved with proper natural lighting systems.
• Lighting costs – almost 65% of the energy costs that are borne are due to Lighting which can be significantly reduced using natural lighting.
• Maintenance costs – Other miscellaneous costs associated with HVAC which included maintenance costs can also be significantly brought down by proper daylight harvesting systems.

Know more about these in this article.

Healthier working conditions

Natural lighting promote better health for the occupants – Research studies has shown that natural light improves health and overall well being of the occupants of a building.

A research at the Cardiff university reported the relationship between natural elements and human productivity and found a 15% increase in the productivity with employees with offices having natural elements compared to employees with offices without having natural elements.

Getting The Most Out Of Daylight Harvesting

Get the basics right and you would be right on your way to improving the daylight design for the building. Get the siting and massing of the building right to have the building positioned to get optimum sunlight if you are constructing a new building. Use proper modeling techniques to test out the lighting conditions with proper fenestrations. Having proper daylighting systems not only reduces energy costs but also improves employees productivity and well being. Hence this is worth the investment. If you are in search for a quality daylighting design expert, please contact us.

The Author is a Solar Consultant and is passionate about Renewable Energy Technologies. https://www.lavancha.in