Rebound Effect

Matthew J. Realff
Matthew J. Realff
Professor, School of Chemical and Biomolecular Engineering Associate Director, Strategic Energy Institute
Read more by Matthew J. Realff

How would you define this big idea?

A rebound effect is created when a perceived positive change in a system leads to another change that is regarded as negative, therefore leading to an offset in the benefits that were anticipated by causing the first change to happen. This has most often been seen in the context of efficiency and overall resource use. For example, increasing the efficiency of lighting of roadways by having a greater output of light per unit of investment in road lighting may not decrease the overall utilization of energy in lighting roads because more roads are lit, which may provide greater overall benefit, but the intended reduction in energy use may not occur. Similarly, increasing the efficiency of cars, as measured in miles per gallon, does not necessarily reduce the amount of gasoline consumed because people adjust to drive further. Essentially efficiency often translates into lower cost per unit function and then the elasticities of the supply and demand curves will determine the overall units demanded, which could lead to greater or smaller overall resource use. Another recent example is gun control, the threat of passing gun control legislation causes the number of guns sold to increase.

Why this big idea is important for sustainable systems?

Understanding the rebound effect is critical for sustainable systems because it is one way that a well-intentioned change can lead to the perverse outcome of increased resource use when it was intended to decrease resource use. It arises due to feedbacks in the system that were not seen, or not of significant magnitude, before the change was made.

Learn more:

T. Princen, The Logic of Sufficiency, MIT Press Cambridge MA, 2005.
A beautiful book that has several examples of the rebound effect and the problems with seeking efficiency rather than sufficiency. Has a number of case studies that document how certain communities have managed to reach a more sufficient lifestyle.

D. Owen, The Conundrum, Riverside Books, NY, 2011.
This book focuses on the rebound effect in different circumstances and shows how difficult it can be to avoid its unintended consequences.

Big Idea: