Energy conservation are efforts made to reduce the consumption of energy by using less of an energy service. This can be achieved either by using energy more efficiently (using less energy for a constant service) or by reducing the amount of services used (for example, by driving less).
Energy conservation is a part of the concept of eco-sufficiency. Energy conservation reduces the need for energy services, and can result in increased environmental quality, national security, personal financial security and higher savings
It is at the top of the sustainable energy hierarchy. It also lowers energy costs by preventing future resource depletion