This is why I’ve been having problems with the Carnot limit recently.
Credit for a particularly exceptional use of this analogy goes to Johns Hopkins Medicine
Media Relations and Public Affairs:.
“Like the hybrid car, cells use oxygen and the internal combustion engine at higher speeds and rely on an electric engine without need for oxygen consumption at lower speeds. Cells consume glucose through its main energy-producing machine, the mitochondrion, when oxygen is ample. But like the internal combustion engine, this process generates pollutants or toxic oxygen molecules. “
Original fluorescence image by IP22.214.171.124 from http://en.wikipedia.org/wiki/File:DAPIMitoTrackerRedAlexaFluor488BPAE.jpg and under a creative commons attribution (CCBY) licence.