"Higher efficiency reduces the cost of cooling. A family that once had only a single air-conditioned bedroom may now choose to install a central unit, and one that suffered in the heat may purchase its first one."
Michaels has terms for these phenomena.
He calls overestimating the effect of more energy-efficient stuff "rebound."
"Technology that improves energy efficiency and reduces its cost means people can consume more good and services that use energy - home electronics, appliances and the like," he said. "And of course, businesses will use additional energy making them."
Which brings to mind the fancy term for increased consumption in response to greater energy efficiency.
You guessed it.