27.04.2010 - Design & Architecture

LED technology conquers the lighting market

One of the most dominant trends at the Light+Building exhibition, which took place in Frankfurt from 11th to 16th April 2010, was the increasing use of LED technology in lighting. With 180,000 visitors, the biennial exhibition showed a growth of eight per cent compared to 2008. This is mainly attributed to rising international interest in this innovation platform for technology, design, architecture and sustainability.

The exhibition highlights the latest developments and future trends in interior and exterior lighting and smart building technology. “Energy efficiency and LED lighting are the two areas that are coming on in leaps and bounds,” predicts Friedhelm Loh, President of the German Electrical and Electronic Manufacturers' Association, ZVEI (Zentralverband der Elektrotechnik- und Elektronikindustrie). We’ve long been familiar with the little LED indicator lights used on many electronic devices. Yet, what exactly these light-emitting diodes are and how they work remains firmly in the domain of specialist technical knowledge. LEDs generate light in quite a different way from conventional light bulbs or fluorescent lamps, which contain substances that glow, generate heat and create the light more or less as a by-product of that heat. A traditional incandescent light bulb generates 5 per cent light and 95 per cent heat, and fluorescent lamps still generate only 20 per cent light compared to 80 per cent heat. So, an enormous amount of energy is wasted. An LED light consists of a transparent case containing several layers of semiconducting material and a microchip. This is then forward-biased (which means that LEDs run on direct current). The light is transmitted directly or through reflection, and the wavelength of the light – i.e. its colour – is determined by the type of semiconductor. LEDs generate very little heat in the process, as there is no filament or other material to be heated up. The only heat generated is within the semiconductor diode. LED lights have numerous advantages: in addition to their energy efficiency, longevity and much smaller size, they are also more robust and able to withstand vibration much better, generate no UV or infrared rays and offer enormous scope for designers – in particular due to their compactness and low heat generation. LED lights are extremely reliable even under difficult conditions. However, it took many years of technological advancement before LED lights became affordable enough to be introduced to a more mainstream market.

At the Light + Building exhibition, major suppliers such as Philips and Osram now present a whole host of LED lighting elements for interior and exterior use. Especially the new E27 and E14 lamps are available in infinite variations ready to take over from standard incandescent light bulbs and energy-saving lamps. Osram’s Parathom® range, meanwhile, offers lamps and spotlights in ‘Warm White’ and ‘Daylight’ colours. These claim to reduce energy consumption by 85 per cent at an average lifespan of 25,000 hours. Philips presents similar lamps in its Retrofit range. They come in a warm white, are dimmable and the range is complemented by Deco LED lamps and the Novallure series designed to replace conventional “candle-style” light bulbs, as used, for example, in restaurants and hotels. Furthermore, manufacturers can supply a range of LED lights and lighting elements for professional use by designers and architects. For the high-end market, Zumtobel is offering its new LED downlighter range Panos Infinity, which combines energy efficiency, design and excellent light quality. Their minimalist form and a light efficiency of up to 77 lumens per watt demonstrate that high-quality LED technology has already overtaken standard compact fluorescent lamps in terms of energy efficiency and light quality. The design by Christopher Redfern brings the successful Panos downlighter range into the present day. Their 1,800-lumen output requires only 27 watts of energy, while the 2,400-lumen version of the Panos Infinity Downlight uses 36 watts, making this LED downlight over 70 per cent more efficient than downlighters using conventional energy-efficiency light bulbs. Erco, from the town of Lüdenscheid in North Rhine-Westphalia, are known for their well-designed architectural lighting and the company is now also moving towards LED lights. Their new range of recessed ceiling luminaires utilising LED lamps is called Quintessence. Kay Pawlik, Erco’s Managing Director, says: “This year’s Light+Building marks a turning point in architectural lighting. After years of anticipation and restriction to specialist uses, LED technology is now finally on the verge of a breakthrough.” W.O. Geberzahn