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1. In Western countries, electricity, gas, and water are not   but necessities. Companies now realize that   want products that will not only work effectively, but also save money.
For most North American households, lighting accounts for 10 percent to 15 percent of the electricity bill. However, this amount can be reduced by replacing an ordinary 100-watt light bulb with an energy-saving  . These bulbs use a quarter of the electricity of standard bulbs and last eight times longer. Therefore consumers can save about US$7 to US$21 per bulb.