Lighting is one of the least energy-efficient practices in the home, with a mere 10 percent of energy used providing actual light, the remainder providing unwanted, unnecessary heat. One of the three main greenhouse gases, carbon dioxide (CO2) is emitted whenever a light is turned on. And given that lighting generally accounts for about a 10th of a homeowner's energy bill, lighting is one of the least environmentally sound aspects of modern living. Yet about two-thirds of all lighting currently installed in the European Union is based on older less efficient technology, when switching to energy-efficient lighting would bring huge savings in energy costs and CO2 emissions. Kathimerini English Edition talked to representatives of Philips and Osram, who together hold the largest share of the market, about trends in energy-efficient lighting in Greece, which appear to be about the same as in the rest of Europe. «Only 6-10 percent of Greek homes use energy-efficient lighting, and in the rest of Europe the figure is not much higher,» said Philips Hellas marketing manager Evangelos Papadodimas. «It has been available in Greece for about 10 years but it is only in the last couple of years that people have begun to switch over.» The main reason is the higher price of energy-saving light bulbs compared to the old incandescent ones, even though average savings amount to about 70 percent due to their lower wattage. «The newer light bulbs pay for themselves within a year, but last on average about 8 years,» said Papadodimas. «If you replace one 100-watt incandescent bulb with a 20-watt energy-saving bulb you save about 12 euros a year.» «An average house in Greece uses about 20 bulbs, at least 10 of which are used for general lighting and burn for a long time. For each 10-bulb change per house, the saving in energy costs for the householder is 120 euros per year, and the saving for the environment is 800 kWh per year,» he said. The on-line Green Consumer Guide says energy-efficient light bulbs offer a better light/heat ratio, as well as reducing energy consumption. Replacing a 100-watt incandescent with a 32-watt compact fluorescent light bulb (CFL) can save at least $30 in energy costs over the life of the bulb. CFLs provide high-quality light without the heat of incandescent bulbs. LEDs (light-emitting diodes) don't heat up like incandescents, last longer and are more energy efficient than both traditional bulbs and CFLs. Still very expensive for the mass market, they are nevertheless being heralded as the light bulb of the future. Halogen light bulbs, however, represent considerable savings over the long term, said Osram's Emmanuela Emmanouilidou. The firm's two basic models in the range, with an average life of 2,000 hours, represent a saving of 4.70 euros for the halogen equivalent (42 watt) of a 60-watt incandescent bulb, and a 12-kilogram reduction in carbon dioxide. «Halogen energy-efficient light bulbs are ideal replacements for ordinary light bulbs as they provide better-quality lighting, last at least twice as long and consume up to 30 percent less power. They have a screw base so are easy to use, they have a similar appearance to ordinary light bulbs and are available in many shapes.» The bigger picture According to Britain's Institute of Lighting Engineers, lighting is contributing to an increase in greenhouse gases - the UK causes 3 percent of global greenhouse gas emissions with only 1 percent of the world's population. To generate 1 kilowatt hour of electricity uses about 0.5 kg of coal and produces 0.9 kg of carbon dioxide emissions. By simply switching incandescent lamps over to other energy-saving lighting technologies, the EU could save 10 billion euros per year, equivalent to 25 million tons of CO2, the consumption of 105 million barrels of oil per year and the annual output of 35 power stations at 2 TWh/yr, according to figures from Philips Lighting Central Market Intelligence. So it seems that if a critical mass were reached in the number of people switching over to «greener» lighting, it could make a difference - there seems to be no excuse for claiming that one household can't make a difference, so why bother? Proper practice Apart from choosing the most environmentally friendly light sources, it is also important to match the proper lamp type to the intended purpose, according to the amount of brightness needed, for example. And to make lighting even more environmentally friendly - turn off those unnecessary lights!