GRENOBLE – Lighting is becoming the largest consumer of electricity in buildings, accounting for 25 percent or more of total costs. At the Leti’s Annual Review this week in Grenoble, France, Alexandre Lagrange at the CEA-Leti Optic and Photonic Department, demonstrated CEA-Leti’s engagement in research leading to smart lighting systems with adaptive and controllable properties.
Due to its high potential for CO˛ abatement, lighting is a fast moving business, and market growth expectations are high.
The white LED efficiency, said Lagrange in his keynote, is currently increasing sharply. Performances are there. But a plateau will be reached soon. There is not much to gain in terms of performances. And looking at the cost trajectory for LED luminaires, margins will drop dramatically. Today, LED cost is about 6$/klm but the cost reduction should be transferred to the customers so margins will be lower.
The white LED efficiency is growing sharplySource: EuroLED 2012
OLED technology is a few years behind in terms of performances. The cost is a blocking point as, in 2011, it was about 20.000$/klm. “It’s another dimension, and the OLED lighting market is not yet foreseen,” noted Lagrange.
Customers want more light, or lumen, per dollar. For that, Lagrange called for more than lumen. This means adding new functions, working on high-quality lighting, developing easy-to-integrate in-house solutions and adding more services through the light.
Lighting has become electronic, and LED should move to smart lighting, Lagrange continued. Intelligent lighting parameters should enable the user to adjust the quality, the quantity and the direction of light.
He commented: “We started with a simple packaged LED. [At Leti] we are adding actuators and smart sensors to detect presence, heat, ambient light and movement, leading to a smart luminaire that should be able to work in a network.”
Smartness goes down towards the light source, stated Lagrange. This
means that, prior to turning on the light, we should add some
intelligence at the building level with movement and light sensors as
well as clocks control lighting. Then, we should make the luminaire
smarter with movement and light sensors, means of communication into the
luminaire for an easier installation and adjustment. And, at the end of
the chain, light sources should include drivers, sensors (device
temperature, color temperature, light level, presence) and
Smartness goes down towards the light source
Eventually, at home, light should be part of a network, and “we should think about cooperation between luminaires or between users and luminaires. Embedded electronics and sensors open the door to high added-value with small added cost,” concluded Lagrange.
CEA-Leti has been working on LED lighting since 2006. Initially, its R&D programs were limited to the “upstream” end of the industrial supply chain, focusing mainly on new semiconductor materials such as gallium nitride or zinc oxide, and unconventional chip technologies such as nanowire-based LEDs. Since then, a variety of new “downstream” projects have been launched to deal with the key issues of thermal management, light extraction and wavelength conversion.
Leti is a partner of SMASH, an EU-funded development project coordinated by Osram Opto Semiconductors GmbH that aims to significantly reduce the production costs of LEDs by enabling the epitaxial growth of nanowire-based LED structures over large areas, using low-cost substrates such as silicon.
Leti is also supporting the CITADEL initiative led by France’s Center for Building Science and Technology (CSTB) in conjunction with other laboratories and the French branch of Philips Lighting. This project is intended to research and promote the optimal use of LED lights in buildings.
A third example is Leti’s engagement in “PACTE-LED”, an LED development project that aims to develop LED-based lamps to directly replace 25- and 35-watt halogen lamps, ensuring similar light quality while using one-fourth as much power.------------------------
If you found this article to be of interest, visit SmartEnergy Designline
where you will find the latest and greatest design, technology,
product, and news articles with regard to all aspects of clean
technologies. And, to register to our weekly newsletter, click here.