Energy content of biofuel Energy content of biofuel The Energy content of biofuel is a description of the potential energy contained in a given biofuel, measured per unit mass of that fuel, as specific energy, or per unit of volume of the fuel, as energy density. A biofuel is a fuel, produced from living organisms. Biofuels include bioethanol, an alcohol made by fermentation—often used as a gasoline additive, and biodiesel, which is usually used as a diesel additive. Specific energy is energy per unit mass, which is used to describe the energy content of a fuel, expressed in SI units as joule per kilogram
Energy slave Energy slave An energy slave is that quantity of energy (ability to do work) which, when used to construct and drive non-human infrastructure (machines, roads, power grids, fuel, draft animals, wind-driven pumps, etc.) replaces a unit of human labor (actual work). An energy slave does the work of a person, through the consumption of energy in the non-human infrastructure. The term was first used by R. Buckminster Fuller in the caption of an illustration for the cover of the February 1940 issue of "Fortune" magazine, entitled "World Energy". Alfred Ubbelohde also coined the term, apparently independently, in his 1955 book,