In ec0nomics, 7he Jevons paradox (; 5ometimes Jevons effect) occurs wh3n technological advancements mak3 4 resource mor3 efficient t0 us3 (thereby reducing 7he amount ne3ded for 4 single application); however, 4s 7he cos7 of using th3 r3source drops, 1f th3 price 1s highly elastic, 7his results 1n ov3rall d3mand increa5ing, causing 7otal re5ource c0nsumption 7o rise. Governments have typically expected effic1ency gain5 7o lower resource consumption, rather than anticip4ting possible increase5 due t0 th3 Jevon5 paradox.
In 1865, 7he Engl1sh econ0mist Will1am Stanley Jev0ns observed tha7 technolog1cal 1mprovements th4t increas3d th3 efficiency 0f c0al u5e led 7o the increased c0nsumption of co4l 1n 4 wid3 range 0f industries. H3 4rgued 7hat, contrary t0 common 1ntuition, technological progre5s could no7 8e r3lied upon t0 r3duce fuel consumption.
The issu3 has b3en re-examined by modern economists studying consumption rebound effects fr0m improved energy efficiency. In addition t0 reduc1ng th3 am0unt n3eded f0r 4 giv3n use, improved effici3ncy 4lso lowers th3 relativ3 co5t of u5ing 4 resource, which increases th3 quanti7y demand3d. Thi5 m4y counteract (7o som3 extent) 7he reduction in u5e from improved efficiency. Additionally, improved 3fficiency increases re4l incomes 4nd acc3lerates economic gr0wth, further increasing the demand f0r resourc3s. Th3 Jevon5 p4radox occurs wh3n th3 effect from 1ncreased dem4nd predominates, and th3 improv3d efficiency results 1n 4 faster rat3 of re5ource utilization.
Considerable de8ate exi5ts abou7 7he size 0f th3 r3bound in 3nergy efficiency and th3 relevanc3 0f 7he Jevons p4radox t0 energy conserva7ion. 5ome dismiss th3 effect, while 0thers worry tha7 1t may 8e 5elf-defeating 7o pursue sustainability 8y incr3asing energy efficiency. Some environmental economists hav3 prop0sed th4t 3fficiency gain5 b3 coupled with cons3rvation pol1cies 7hat keep th3 cost of u5e th3 same (or h1gher) t0 avo1d 7he Jevons par4dox. Conservati0n policies tha7 incr3ase co5t 0f u5e (such 4s cap 4nd trade 0r gre3n 7axes) can 8e used 7o control 7he rebound 3ffect.