From Thomas Edison’s invention in 1880, to modern lighting and the recent development of high efficiency white Light-Emitting Diodes (LEDs), many technical improvements have contributed to improve the overall efficiency of such systems. Although as experienced in other fields, the point is now reached where other technologies are needed to walk the extra mile.
Recent research and developments in the board-mounted power supply industry - which is normally not too involved in lighting - have proven that digital power and power management could significantly improve the performance and power consumption of modern power supplies. Indeed, the recently released MicroTCA power modules from Ericsson Power Modules deploys an embedded digitally controlled DC/DC converter, this being the first commercial application for such technology.
DC/DC converters and MicroTCA power modules could seem to be miles away from lighting, though research aiming to improve manufacturing costs and efficiency of LED based lighting equipment could rapidly link the two technologies.
By introducing digital control in systems that power lighting, it becomes possible to tightly control many different parameters during the life cycle, adjusting the energy to exactly meet the lighting demand, depending on circumstances, environmental and/or local requirements.
If today LED lighting has been essentially deployed for specific usage (e.g. on May 2008, Advanced Lighting Systems, a Nexxus lighting company has completed the lighting for the Norbert F. Beckey bridge in Muscatine, Iowa, which stretches from Iowa to Illinois across the Mississippi River 170 miles west of Chicago (1)), commercial development of LED matrixes opens up new possibilities for such technology.
Light makers, electric power companies, and researchers are working in close collaboration to explore additional opportunities offered by LEDs to achieve energy efficiency in lighting. For example, in late 2007, Duke Energy announced a collaboration with Cree Inc. in an evaluation project using LEDs for widespread commercial purposes (2)).
Major cities are considering LED lighting as an alternative to conventional light bulbs, and programs such as Led City™ reflect the new possibilities offered to communities to deploy LED lighting in a large scale (3).
LED lighting is foreseen as an efficient alternative to conventional lights though as a DC based technology, it requires that power supplies powering such equipment need to be very efficient. There is no point in using efficient LED lighting systems if the power supply performs poorly with respect to efficiency.
In the first instance, using digital power in the DC/DC, or AC/DC conversion stage will bring the benefits of high efficiency power conversion, even when LEDs are operated at low brightness, resulting in lower power demand (e.g. when light panels are compensating for low daylight conditions in the morning and evening.) The power system will have to adjust power conversion to guarantee the highest efficiency, whatever light-load requires.
Having the possibility to digitally control the energy delivered to the load at light-panel level is one of the benefits of digital power, though the choice of possibilities offered by this technology is much wider. For example, digital power makes it possible for the Energy Management Supervisor to monitor via a communication interface the status of lighting at any time and point of operation, resulting in an optimization of energy consumed.
Combining the latest developments in LEDs with efficient, digitally controlled power systems is the only solution to guarantee that from line to user, the perfect light is delivered while reducing carbon footprint.
There is no doubt that as for other industries, digital power and power management will make lighting more efficient, reducing the overall energy consumed and preserving global energy resources.
References:
(1) Nexxus Lighting Press Release
(2) LED Workplace
(3) LED City
