For example, a family that buys a fuel-efficient car may not be reducing their carbon footprint if they regularly drive the vehicle more often than they used the previous car.
Discussing the report, its chief author Steve Sorrell said: "If we do not make sufficient allowance for rebound effects, we will overestimate the contribution that energy efficiency can make to reducing carbon emissions.
"This is especially important given that the Climate Change Bill proposes legally-binding commitments to meet carbon emissions reduction targets. We need to get the sums right."
Established in 2004, the UKERC was created on the recommendation of the government's chief scientific advisor to compile information on sustainable energy usage.
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