Help promote Energy Explained with the outreach toolkit

Energy Efficiency and Conservation

Everyone uses energy

People use energy each day 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 everyone's lives.

Did you know?

Energy Star logo The ENERGY STAR® label on appliances and electronic equipment identifies energy-efficient products.

Efficiency and conservation are different but related

The terms energy efficiency and energy conservation have distinct meanings:

  • Energy efficiency is using technology that requires less energy to perform the same function. Using a compact fluorescent light bulb that requires less energy instead of using an incandescent 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.

Last updated: December 15, 2016

Energy conservation and energy efficiency both relate to the use of energy

Did you know?

With the help of the ENERGY STAR® program, as of December 2014, families and businesses have saved $360 billion on utility bills, while reducing greenhouse gas emissions by 2.5 billion metric tons since 1992.

Energy conservation occurs by reducing the use of energy services. Energy conservation can include turning off the lights or setting the thermostat lower in the winter.

Energy efficiency means using less energy to provide the same level of energy services. Examples include replacing incandescent light bulbs with compact fluorescent bulbs and purchasing energy-efficient appliances and electronic equipment.

Energy efficiency is different from energy conservation

Sometimes energy conservation is mistaken for energy efficiency. Consider an office building with signs that read, "Be more energy efficient—use the stairs instead of the elevator." If people follow the advice of the signs and take the stairs instead of the elevators, is this an increase in energy efficiency? No. The elevator is being used less often, but the elevator still uses the same amount of electricity when it is used, so taking the stairs is actually energy conservation.

The rebound effect complicates energy conservation efforts

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

Did you know?

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

There are many ways to conserve and use energy more efficiently

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

The Database of State Incentives for Renewable Energy and Efficiency (DSIRE) is a comprehensive source of information about financial incentives for energy conservation efforts and energy-efficient product and equipment purchases.

Last reviewed: November 12, 2015