Rebound Effect (conservation)

Rebound Effect (conservation)

In conservation and energy economics, the rebound effect (or take-back effect) refers to the behavioral or other systemic responses to the introduction of new technologies that increase the efficiency of resource use. These responses tend to offset the beneficial effects of the new technology or other measures taken. While the literature on the rebound effect generally focuses on the effect of technological improvements on energy consumption, the theory can also be applied to the use of any natural resource or other input, such as labor. The rebound effect is generally expressed as a ratio of the lost benefit compared to the expected environmental benefit when holding consumption constant. For instance, if a 5% improvement in vehicle fuel efficiency results in only a 2% drop in fuel use, there is a 60% rebound effect (since (5-2)⁄₅ = 60%). The 'missing' 3% might have been consumed by driving faster or further than before.

The existence of the rebound effect is uncontroversial. However, debate continues as to the size and importance of the effect in real world situations. There are three possible outcomes regarding the size of the rebound effect:

1. The actual resource savings are higher than expected – the rebound effect is negative. This will normally occur if the government mandates the use of more resource efficient technologies that are also more costly to use, but not if the increase in efficiency reduces costs
2. The actual savings are less than expected savings – the rebound effect is between 0% and 100%. This is sometimes known as 'take-back', and is the most common result of empirical studies on individual markets.
3. The actual resource savings are negative – the rebound effect is higher than 100%. This situation is commonly known as the Jevons paradox, and is sometimes referred to as 'back-fire'.

The full rebound effect can be distinguished into three different economic reactions to technological changes: The direct rebound effect refers to increases in consumption of a good because of the substitution effect from lower cost of use. Indirect rebound effects come about from the income effect as decreased costs enables increased household consumption of other goods and services. Economy wide effects occur because improved technology creates new production possibilities and increases economic growth.

In order to avoid the rebound effect, environmental economists have suggested that any cost savings from efficiency gains be taxed in order to keep the cost of use the same.