Efficient energy use, sometimes simply called energy efficiency, is using less energy to provide the same level of energy service. An example would be insulating a home to use less heating and cooling energy to achieve the same temperature. Another example would be installing
fluorescent lights and/or skylights instead of incandescent lights to attain the same level of illumination. So efficient energy use is achieved primarily by means of a more efficient technology or process rather than by changes in invidual behaviour.
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