The DALI Alliance has published a White Paper to explain as an advanced lighting-control system based on a global standard such as DALI can help designers, architects and building owners to address a wide range of lighting-related issues, including sustainability, the circular economy, energy consumption, data and analytics

With the world facing an unprecedented climate crisis and rising energy costs, all businesses need to become more sustainable and reduce their energy consumption and carbon footprint – not least when it comes to lighting, which accounts for around 15% of global electricity consumption and 5% of worldwide greenhouse gas emissions. Sustainability in lighting starts with reduced energy consumption. Use of sophisticated lighting control systems, enabled for example by DALI, builds on the gains achieved through the use of LED light sources as well as simple control techniques like switching and dimming. Sustainability also includes factors such as reduced materials usage and recycling in line with the UN’s Sustainable Development Goal 12: Responsible Consumption and Production.

DALI’s role in future-proofing

In the lighting industry, there is an increasing drive for replaceable components that extend the service life of luminaires. If suitable components are available – and if replacement is possible – then luminaires can be repaired, or upgraded with new and improved features and functions. Here, the strength of DALI as a globally standardized protocol comes to the fore. The DALI-2 certification program, developed and maintained by the DALI Alliance, has created an ecosystem of interoperable products from multiple vendors. This ensures the long-term availability of compatible components, and avoids issues associated with vendor lock-in and reliance on proprietary solutions that may not be supported in the future.

DALI-2 also provides backwards compatibility with earlier product generations. Rather than being a temporary solution or a fast-changing trend, the DALI protocol has been around for decades, supported by all major players in the lighting industry. New extensions and certification programs (such as DALI-2, D4i and DALI+) are forward-looking and – crucially – standardized. DALI is inherently flexible and lends itself to future-proof designs that extend the useful life of a lighting control system. Changes to the design of a DALI system and how it is operated can often be dealt with by software reprogramming, rather than having to rewire or replace luminaires and other equipment. This could, for example, allow a building operator to easily change the utilization of space to accommodate new tenants. Future-proofing is enabled at the luminaire level by the Zhaga-D4i connector system, which facilitates plug-and-play replacement of luminaire-mounted sensors and communication nodes.

Zhaga-D4i combines the standardized mechanical interface from the Zhaga Consortium with the communication and power requirements specified by the DALI Alliance as part of the D4i certification program. Zhaga-D4i certification has enabled an ecosystem of interoperable luminaires and control devices. This allows luminaire owners to easily update their fixtures, protect their investment, sustainably extend the life of the luminaire, and keep pace with fast-moving developments in digital networking and sensing technologies.

A wireless future?

While wired systems provide network stability and reliable connectivity, there is a growing interest in wireless capabilities, which must be considered in future-proofing any system design. Two approaches have been developed that combine the DALI protocol with wireless technology.  The standardized gateways approach enables wired DALI networks or D4i/DALI-2 luminaires to be incorporated into certain wireless ecosystems, such as Zigbee and Bluetooth Mesh. The DALI+ approach enables DALI to be used over wireless and IP-based networks, thus increasing choice and flexibility.

The DALI Alliance is currently developing certification programs for both the standardized gateways and DALI+ with Thread as the carrier. With a wireless lighting control system, it’s possible to position wireless control devices without the restrictions of having to run network cables (although power is still required). This has the potential to increase flexibility while also making it easier to scale up systems and add new devices. With no new cabling, labour and material costs are reduced, and there’s less damage to the building.

However, there are other scenarios where a wired solution is preferred or mandated. In different circumstances, hybrid solutions may be desirable. DALI provides choice and keeps future options open by enabling wired and wireless networks to operate together. For example, wireless DALI+ networks can incorporate bridges that provide a link to a wired DALI network, with DALI used throughout as the communication language. DALI+ over an IP-based carrier such as Thread also opens the possibility to integrate the lighting system with other functions via a building’s IT infrastructure.

Minimising energy consumption with lighting control and the power of data

Even when using efficient light sources, most commercial buildings have poor lighting efficiency because the lights are on even when the illuminated spaces are not in use. Lighting often accounts for around 20 to 30% of total energy costs, depending upon the building type, so the potential savings are very significant. An effective approach is to adopt an automated DALI lighting control system, with sensors to detect occupancy, movement and daylight levels. The more sophistication, more functions, and more intelligence we can add to a lighting control system (e.g: PIR sensors, sensors coupled with occupancy-based data analytics etc), the greater the energy savings that are possible. Of course, this requires suitable software that is intuitive and user-friendly, and straightforward controls and user interfaces that building occupants will be able to understand and use.

DALI’s role here is to standardize the functionality of input devices such as switches, sliders and push-button devices. Recently, several DALI data specifications have been developed to standardize the location and format of new types of data that can be stored in control gear such as LED drivers. This data, which relates to light sources, luminaires and the drivers themselves, can be used for asset management, energy monitoring, diagnostics, predictive maintenance, and many other applications. Perhaps most importantly, some drivers have the capability to report real-time energy usage and power consumption.

Designers, architects and building owners must consider a wide range of lighting-related aspects including sustainability, the circular economy, energy consumption, data and analytics. An effective DALI lighting control system will handle all of these, bringing peace of mind to all concerned. It will help meet external requirements, such as legislation for emergency and roadway lighting, while also ensuring the lighting achieves the appropriate performance requirements. An advanced lighting-control system, based on a global standard such as DALI, will reduce energy usage and carbon footprint, as well as decreasing total cost of ownership.  As a global industry organization focused on standardization and market acceptance, the DALI Alliance enables the broad adoption, scale and technology leadership needed by the industry.

Download the White Paper here