At its headquarters in Leverkusen, Bayer MaterialScience has replaced five conventional 150-watt street lights with state-of-the-art LED lights that each consume only 58 watts of power. This has cut energy use for lighting on this section of road by some 60 percent. Carbon dioxide emissions have been lowered by more than one ton per year. At the same time, motorists and pedestrians have no need to fear about their safety – lenses made of the transparent polycarbonate Makrolon LED from Bayer ensure the LED light is focused precisely and the road is well lit.The new street lights are part of the "Eco StreetLine" range developed by Hella KGaA Hueck & Co in conjunction with Bayer MaterialScience. The two companies have been collaborating for decades in automotive lighting and were able to harness the knowledge gleaned during this time in the modular design for the street lighting system. This application is just one example of the expertise that both companies have in lighting technology and that they are showcasing at the Light + Building trade fair.
In Germany alone, the annual power consumption from operating over nine million street lights is around 4,000 gigawatt hours. To help conserve resources and protect the climate, local authorities are thus being called upon to make significant cuts in energy consumption and CO2 emissions for lighting public roads and spaces.
"Simply by using energy-efficient LED technology, it is possible to reduce energy consumption by up to 70 percent compared with conventional street lights," explains Paul Meier, head of Hella Industries. "This benefits local authority budgets and the environment alike." The company estimates that the additional costs for an LED street light are generally recouped after less than three years. Depending on the ambient lighting conditions, the street lights can also be dimmed by as much as 50 percent, thus offering additional potential savings. The long service life of LED modules of approximately 50,000 hours also plays a role in reducing operating costs.
For these and other optical applications for LED technology, Bayer MaterialScience has developed special polycarbonate materials marketed under the name Makrolon LED. Lenses made from this material concentrate and focus LED light in such a way that roads and footpaths are lit up brightly and drivers and pedestrians have good visibility.
"Makrolon LED also offers considerable freedom in manufacturing complex lens shapes and remains transparent even with a thicker coating," says Dr. Klaus Reinartz, marketing director LED at Bayer MaterialScience in Europe, Middle East, Africa and Latin America. It boasts greater rupture strength and temperature stability than other plastics.
