May be even 50 years back, lighting was thought to be just the means for illuminating a space or an object. However, today the concept has vastly changed. Nowadays, lighting is considered as an influencer, an enabler and a way to tickle imagination. See at home, watch on the road, observe in the theatre, experience in the shopping mall or feel in the hotel… everywhere light plays a vital role not only to create ambience, but also it extends your engagement, it deepens your involvement, it uplifts your enthusiasm and it provides relaxation for your stress relief.

Although, it is quite unfortunate that to common people, still energy cost is the primary determiner for lighting, people with even a little sense of aesthetics are now quite careful about using lights considering their other attributions including Colour Temperature, Colouring Rendering Index (CRI) and of course adaptability. Advent of LEDs and development of their control systems have not only made the application of lighting much easier but also enhanced the accuracy & appropriateness of their application. Contextually, IoT is also one of the game changers in this regard.

Out of different branches of lighting, these days architectural lighting has emerged as a distinguished field and the most interesting aspect of it is that – its application is no longer limited to just for illuminating any particular architectural object. In the sense, its application is much more subtle and diverse. Every good lighting designer invariably and (often) unknowingly uses the concepts or principles of architectural lighting design in his/her projects.

Thus, contrary to the conventional belief that the architectural lighting is used for architectural objects only, at present its definition has widened much, and of late this field may be viewed as an integrated approach in combination with the daylight to facilitate ‘human action’. The phrase “facilitate ‘human action’” is the result of various mental exercises like imagination, creation, infusion, boosting and accommodating the natural light. More simply, architectural lighting is to complement the natural light with more value addition (in some cases). Thus, it is a modified recreation of the nature may be inside or outside the premises (during absence of natural light).

Utility of architectural lighting           

Obviously, architectural lighting is need-based but as already discussed, it spreads its wings much beyond – embracing aesthetics, ergonomics and energy conservation. Modern sensors allow it to perfectly integrate with daylight according to the Time of the Day (ToD).

The utility varies from application to application and it is based on the ToD, e.g., a restaurant may have an extended outdoor space where people enjoy sitting under the open sky. As the daylight fades, more light is needed to maintain proper visibility, where modern sensors automatically increase the intensity of artificial lights.

As it is need-based, the application of architectural lights varies from project to project. At some places like the entry points of hotels, architectural lights are used to welcome the customers. Inside a temple or church, it is cool to create the meditative mood. Shops are generally filled with bright lights (close to daylight) as the shoppers should be able to recognise colour of the objects properly, and in big retail stores & malls they should experience proper illumination in the aisles. In car parking areas too, which are normally a bit secluded places and sometimes wet due to seepage from the upper parts of the buildings (a very common scene in India), bright daylight is absolutely essential, however, continuously keeping them ‘on’ increases the energy bill, thus human-movement sensors are fixed there – whenever people enter the area all lights glow in full capacity, later, after the people leave the area those lights are automatically dimmed.

“The aim of the study is to apply an innovative mix of methods to create a holistic approach to lighting planning which can then function as a seal of quality in the lighting industry.”

– Prof. Ellen Kathrine Hansen Head of Lighting Design,  Aalborg University

In general, designers use around 2700 K colour temperature for Living Rooms, Dining Rooms and Kitchens, around 3000K for Washrooms, Entry Points and Outdoors, around 5000K for Basements and Garages. Offices generally need 3100 K to 4500 K depending on the types of the activity. However, the selection of colour temperature and colour rendering index depends on many other factors. Better CRI (Colour Rendering Index) is very important in shops, doctors’ chambers, laboratories etc. Higher the CRI value better is the designer’s light selection in those places. Yet another very important aspect of architectural lighting is daylight integration on which many research and development works are going on across the world.

As the daylight fades, more light is needed to maintain proper visibility in an open-sky restaurant…

A notable R&D activity on daylight integration

Aalborg University in Copenhagen has been working on an interesting project for the last three years. According to the university, the layman’s description for the project is, “Investigations of how the qualities of dynamic daylight can be complemented through smart electrical lighting in offices.” More elaborately, the university states, “The aim is to investigate potentials in combining daylight and dynamic lighting technology in architectural lighting solutions and to validate how this design approach can contribute to better health and well-being. This is investigated through holistic and new design/experiments and technical solutions in real cases/projects based on qualitative and quantitative criteria. A mixed method approach will be defined to test and validate the hypothesis. Methods like measurements and calculations of light levels, CCT, illuminance, exposure time will be employed as well as observations through videos and photo registration, anthropological interviews and questionnaires. The luminaire and component manufacturers Tridonic, iGuzzini, Fagerhult and Zumtobel have teamed up with Aalborg University in a unique collaboration. The project is joint with other projects in the Lighting Design Research Group LiD_RG.”

At entry points of hotels, architectural lights are used to welcome the customers…
At entry points of hotels, architectural lights are used to welcome the customers…

“Rethinking Light” was the idea that inspired these leading companies in the lighting industry to join forces in supporting the new fundamental research into dynamic lighting.

According to a joint press note by Tridonic, iGuzzini, Fagerhult and Zumtobel, the Double Dynamic Lighting (DDL) research project sets the guidelines for comfortable illumination of workplaces by combining direct and diffuse dynamic daylight and artificial light. The new approach of DDL will have a positive impact on perceived atmosphere, visual comfort and work engagement. The results demonstrate the potential to use new sensor and lighting technologies to meet human needs. The project team produced proposals for lighting scenes based on the natural course of the daylight as well as current sky conditions. By exploring how a responsive lighting technology that reacts to and complements daylight inflow can reconnect man and nature, the findings can help in forming a more holistic design approach in the future.

“Working on a major project with different partners always augments the quality and relevance of the results. The set-up of this project was especially interesting, because some of the partners are actually our competitors.”

– Karin Zumtobel-Chammah, Chairwoman Supervisory Board, Zumtobel Group AG

The project is examining the spatial conditions in a dynamic lighting environment and their influence on the well-being of users. Practical design guidelines are being developed, tested and implemented in a series of investigations. This work is being conducted in existing working environments with dynamic light, in lighting laboratories at Aalborg University and in interactive, three-dimensional computer models.

“The aim of the study is to apply an innovative mix of methods to create a holistic approach to lighting planning which can then function as a seal of quality in the lighting industry.”

– Henrik Clausen, Director, Fagerhult Lighting Academy

The results of the field study demonstrate that it is possible to define dynamic light settings in response to the dynamics of daylight through a combination of direct and diffuse lighting. DDL was validated to have a positive impact on perceived atmosphere, visual comfort, and work engagement compared to static lighting. In general, it was confirmed that the combination of directional task lighting and diffuse ambient lighting in response to sky types and measured daylight levels in the workspace was preferred to standard static diffuse lighting.

An analysis of responses from interviewees reveals a large difference in perceived visual comfort between dynamic and static lighting periods, indicating that working with light zones and with direct and diffuse lighting components and uneven light distribution enable a high level of visual comfort to be achieved. The industry partners added their practical application knowledge and worked hand in hand with the university.

Prof. Ellen Kathrine Hansen, Head of Lighting Design in the Department of Architecture, Design & Media Technology, said about the study, “The aim of the study is to apply an innovative mix of methods to create a holistic approach to lighting planning, which can then function as a seal of quality in the lighting industry. A combination of biological, aesthetic and functional aspects will form the basis for the design process.”

It is quite interesting to note that four globally renowned lighting companies are supporting this project. But why are they doing so?

Focusing on the reason behind their involvement to this research project, Karin Zumtobel-Chammah, Chairwoman Supervisory Board, Zumtobel Group AG, said, “A fundamental element of our DNA is our desire to improve health and well-being by providing the best possible light for both people and the environment and by customising lighting solutions to the different areas of application. And of course, our research and development projects constantly aim to achieve these improvements.”

“In the first instance it will be ‘all of us’ living and working in spaces illuminated by applied DDL design guidelines who will benefit from the DDL research findings.”

– Peter Roos, Product & Project, Solutions Director, iGuzzini

“We identified a great overlap between our research topics and the DDL project, so we were convinced that the findings of this research on combining daylight and dynamic lighting technology would contribute to better health and well-being, and would help us understand certain topics much better. Working on a major project with different partners always augments the quality and relevance of the results. The set-up of this project was especially interesting, because some of the partners are actually our competitors. But since all of us were purely interested in investigating how the combination of daylight and dynamic lighting can contribute to better health and well-being, we were able to join forces and drive industry knowledge forwards,” she added further.

Describing the cause of their interest in the Aalborg University’s project, Henrik Clausen, Director, Fagerhult Lighting Academy, said, “For us it’s also about knowledge. It is a challenge to enhance our general lighting knowledge. We need to do that in order to take advantage of all the possibilities for health and well-being that lighting can give us.”

“We need to educate to create better awareness of how daylight and electric light function together. To get a handle on how to combine the dynamics of daylight and the dynamics of electrical light in the same installation. That’s the basis of Double Dynamic Lighting. We need to spread this knowledge of how to combine daylight and electric light among lighting professionals in terms of design, planning, application and sales. We have been working with Aalborg University on the research side of the DDL project because everything we do in product development and in sales is geared to bringing evidence-based lighting solutions to the market. Now we are preparing to bring knowledge to our partners, our staff and students in order to give them all a competitive advantage in the (still static) lighting market,” he continued.

“The first installation set up at Aalborg University, is a great model for us and we’re continually integrating the research in our installation at our headquarters and enabling our partners to have a DDL installation at their locations.”

– Hugo Rohner, Chief Executive Officer, Tridonic

Commenting on their idea behind joining hands with the University’s research team, Peter Roos, Product & Project Solutions Director, iGuzzini, said, “iGuzzini has always considered light as a tool for social innovation that can improve people’s lives and well-being at every moment of every day. That is why our vision is ‘Social Innovation through Lighting’ and the reason why we have been conducting research on biodynamic light together with leading universities and institutes worldwide since 1988.”

“The idea of the DDL research is to find new lighting design guidelines for workspace lighting, which will improve the well-being of end users. So in the first instance, it will be ‘all of us’ living and working in spaces illuminated by applied DDL design guidelines who will benefit from the DDL research findings. We at iGuzzini believe that the lighting design community together with architects and lighting professionals will embrace the idea of Double Dynamic Lighting to create beautiful spaces we’ll love to live in,” he continued.

Detailing on their participation in the Aalborg University’s research activity, Hugo Rohner, CEO Tridonic, said, “As a technology company of the lighting industry, Tridonic enables new solutions for customers and partners. DDL is a wonderful new challenge for us. We are transferring this fundamental research into solutions for our business partners. The first installation, which was set up at Aalborg University, is a great model for us and we are continually integrating the research in our installation at our headquarters and enabling our partners to have a DDL installation at their locations. In this way, we can learn more and continually develop the technology, which is needed to implement DDL. We are sure that DDL will pave the way to lighting solutions, which will provide individual answers to human needs and requirements.”

Conclusion

The current trend of logical integration of daylight in architectural lighting will continue with more vigour as the renowned lighting companies are taking keen interest in this regard. In this article, I have narrated only one research project, but there are many others. The research outcomes are continuously being implemented in practice. So, in the coming days, the architectural lighting will undergo many changes, designers also will get more tools to improve efficacies of their plans.