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EETE DEC 2013

LED LIGHTING New generation controls offer huge benefits for indoor lighting By Dr Andy Davies Technological advances in monitoring and control solutions for indoor lighting offer designers, engineers and managers an array of benefits from significant reductions in a building’s energy consumption, and the associated cut in CO2 emissions, to unrivalled dynamic control of all lighting output. Innovative lighting systems are inherently flexible and offer completely customisable solutions for every client. There is huge potential to make significant savings on energy costs by taking control of indoor lighting. Of all the controllable lighting sold in Europe today 75% is currently not being controlled Fig. 1: Harvard Engineering’s EyeNut LED-lighting control infrastructure. by anything more sophisticated than an on/off switch. As lighting accounts directly for 50% of the electricity consumed in Europe’s office buildings, control of this expenditure would be hugely beneficial to those organisations wishing not only to cut energy costs but also boost their green credentials. Traditional lights are extremely energy inefficient or lack controllability. For instance, incandescent light bulbs convert less than 5% of the energy they use into visible light and the remaining energy is converted into heat; an unwanted output and unnecessary expense in offices that then have to rely on air-conditioning to regulate the temperature. Incandescent lights also have much shorter life spans than many of the alternatives. With an average life span of around 1,000 hours, the maintenance and replacement costs of these light sources has to be taken into consideration when compared with compact fluorescent lights, which have an expected life span of up to 10,000 hours and LED lamps that offer up to 100,000 hours. Fluorescent lights will convert about 22% of power input into visible light and produce less heat but they require a ballast and their life span is greatly reduced when switched on and off regularly. They also do not have a dimming capacity. Fluorescent lights may be more energy efficient than incandescent lights but, again, they lack controllability. LEDs address both these issues by offering an energy efficient option that is easy to control. However it is only with the recent developments in monitoring and control systems for indoor lighting that the full potential of LEDs can now be realised. This new generation of lighting controls has been instrumental in overcoming a number of challenges faced by the earlier generation controls. Early generation lighting controls, such as DALI and Analogue 1-10V, may be effective in reducing energy consumption but are particularly difficult to commission. Specialist engineers, who can command daily fees of between £600 and £1,000, are required to configure an early generation control system. As this task can take several days this cost alone makes these systems financially unattractive. In new builds configuration of these early generation systems may be carried out in vacant sites before the exact occupancy patterns are known. Based on these assumptions it is highly unlikely that the best energy saving strategies will have been programmed into the system. To optimise the full energy efficiency potential, reconfiguration is often required, however this expense is even more difficult to justify as these controls have no means to monitor their own performance and so their true effectiveness is impossible to ascertain. The new generation of indoor lighting systems which have been recently launched into the market offer control and monitoring capabilities that overcome these challenges and help to optimise the full potential of energy efficient lighting units, such as LEDs – see figure 1. These new solutions can be incorporated into a new build at the design stage or easily retrofitted into existing sites as part of a refurbishment scheme and through wireless networked controls the new intelligent lighting solutions eliminate the need for expensive rewiring of existing buildings and the inevitable disruption to normal business operations. The ability to retrofit these new wireless systems into existing sites is a significant advantage, especially taking into consideration the fact that of all the buildings that are expected to be here in 2050 80% have already been built. One of the most time-consuming tasks associated with commissioning existing lighting control systems, namely the recognition and addressing of individual lights within a scheme, is overcome by new generation solutions that use RFID functionality. Each luminaire can be scanned into the system by using the RFID scanner, or an App on a tablet or smartphone. The intuitive, user-friendly Graphic User Interface (GUI) then has the ability to map each light within the system; it is this innovative technology that allows for the unrivalled control and flexibility of the latest lighting solutions. Control systems that use the open protocol ZigBee mesh network can be operated remotely through the internet via smartphones or computers. This open protocol also offers robust protection against communication breakdown between two devices on the same network, an issue that had previously caused nervousness with earlier wireless technology. Further network security features can include the adoption of remote server hosting, an option often available through the provider of the control system. Dr Andy Davies is business development manager for indoor controls at Harvard Engineering - www.harvardeng.com 26 Electronic Engineering Times Europe December 2013 www.electronics-eetimes.com


EETE DEC 2013
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