ReboundEffekt

ReboundEffekt, often written as Rebound effect or Rebound-Effekt, is a concept in energy economics that describes how improvements in energy efficiency do not always translate into proportional reductions in total energy consumption. When the operating cost of an energy service falls, users may increase the quantity or intensity of that service, and savings can spill over into other energy-using activities. The phenomenon is typically partitioned into direct, indirect, and economy-wide rebound effects.

Direct rebound occurs when a more efficient appliance or vehicle lowers the cost per unit of service, leading to increased use of the same service (for example driving more miles in a fuel-efficient car or leaving lights on longer). Indirect rebound happens when money saved on energy services is spent on other goods and services that consume energy. Economy-wide rebound covers broader macroeconomic responses, such as price adjustments, investment in energy-using equipment, and general economic growth that raises total energy demand.

Estimates of the rebound vary widely by sector, technology, and region. Direct rebound for household energy can range from about 10 to 30 percent of the expected savings, while indirect and economy-wide effects can add substantially, sometimes offsetting a large portion of the initial gains. In rare cases, a backfire occurs where total energy use rises.

The ReboundEffekt is a factor to consider in energy policy and life-cycle assessment. It does not negate the environmental benefits of efficiency but can affect the cost effectiveness of efficiency programs. Policy responses include complementary demand-side management, energy pricing, and recycling of savings into efficiency investments.