energy conservation, saving energy, energy efficiency

The two main ways to use less energy more wisely are energy conservation (or saving energy) and energy efficiency. Many people think these terms mean the same thing, but they are different.

Energy conservation (saving) is any behaviour that results in the use of less energy. Turning the lights off when you leave the room and recycling aluminium cans are both ways of conserving energy. Energy efficiency is the use of technology that requires less energy to perform the same function. A compact fluorescent light bulb that uses less energy than an incandescent bulb to produce the same amount of light is an example of energy efficiency.