Con·serf·fi·cien·cy

\kən-ˈsərv-ˈfi-shən-sē\ noun  1. Using fewer energy services while making remaining services more effective at the same time  2. Conservation and efficiency in tandem  3. Using less energy more effectively

Policies that concentrate simply on energy conservation (using fewer energy services) or energy efficiency (making energy services more productive) are not as effective as policies that employ both modes of energy reduction together.  For instance, moving closer to work in order to cut your daily commute in half, while at the same time driving a car with half the gasoline consumption, would shrink your gasoline consumption to just 1/4 of its original value.

Click on the McKinsey Abatement Curve below to link to the full-size image shown in Dr. Muller's talk.