Rebound Effect

First described by economist William Stanley Jevons in 1865 for coal: improving a technology’s efficiency tends to increase its total consumption because it becomes more affordable and more widely used. Three forms: direct rebound (using more of the now cheaper service, e.g. driving more with an efficient car), indirect rebound (money saved reinvested in other consumption), macroeconomic rebound (innovation spreads use on a large scale). Studies (Greening, Greene & Difiglio 2000; ADEME) estimate direct rebound at between 10 and 30 % depending on use. For air conditioning: once installed, equipment is used longer and at a lower setpoint than expected, worsening SEER’s stated performance in practice.