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Use of energy explained Energy efficiency and conservation

Everyone uses energy

People use energy for transportation, cooking, heating and cooling rooms, manufacturing, lighting, entertainment, and many other uses. The choices people make about how they use energy—turning machines off when they're not using them or choosing to buy fuel-efficient vehicles and energy-efficient appliances—affects the environment and people's lives.

Energy efficiency and energy conservation are related but different

Sometimes people confuse energy efficiency with energy conservation. When someone follows the advice on a sign that says, "Be energy efficient—use the stairs instead of the elevator," are they increasing energy efficiency? No. The elevator will operate less often, but it will still use the same amount of electricity when it does operate. Using the stairs instead of an elevator is energy conservation. Two or more people using the elevator at the same time is more efficient than just one person using it.

  • Energy efficiency is using technology that requires less energy to perform the same function. Using a light-emitting diode (LED) light bulb or a compact fluorescent light (CFL) bulb that requires less energy than an incandescent light bulb to produce the same amount of light is an example of energy efficiency.
  • Energy conservation is any behavior that results in the use of less energy. Turning the lights off when leaving the room and recycling aluminum cans are both ways of conserving energy.

did youknow


The ENERGY STAR® label on appliances and electronic equipment identifies energy-efficient products. Since 1992, ENERGY STAR® and its partners have helped save American families and businesses about 4 trillion kilowatthours of electricity while also achieving broad emissions reductions—all through voluntary action.

The rebound effect complicates energy conservation efforts

If demand for energy services did not change, then improving energy efficiency would reduce energy consumption. However, some energy efficiency improvements might not reduce energy consumption overall. For example, although appliance efficiency standards and building codes have increased energy efficiency, consumers could offset these gains by buying larger homes or more and larger appliances. This offset is called the rebound effect.

We can conserve and use energy efficiently in many ways

The U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, is a comprehensive source of information on energy conservation and efficiency policies, programs, and energy education.

The Database of State Incentives for Renewables and Efficiency® is a comprehensive source of information on financial incentives for energy conservation efforts and energy-efficient product and equipment purchases.

The ENERGY STAR® program is the U.S. government-backed symbol for energy efficiency, providing simple, credible, and unbiased information that consumers and businesses rely on to make well-informed decisions. The program is a source of information on energy-efficient products and on financial incentives for purchasing them.

did youknow


People can do their own home energy audit. The ENERGY STAR® Home Energy Yardstick helps people compare their home's energy use with similar homes across the country. Home Energy Yardstick also provides recommendations for energy-saving home improvements.

Last updated: December 8, 2020