Jevon’s Paradox

(also sometimes spelled / misspelled? Jeavon).

From Wikipedia, the free encyclopedia:
In economics, the Jevons Paradox is an observation made by William Stanley Jevons, who stated that as technological improvements increase the efficiency with which a resource is used, total consumption of that resource may increase, rather than decrease…

Thus it is a dangerous folly to simply improve efficiency, think hybrid gasoline powered cars. Many, unfortunately including most policymakers, constantly harp on “technical improvements” as a way out of our energy problems. We know that this will likely increase demand. Chalk it up as another victory for the law of unintended consequences.

See also, Pigovian tax.