Abstract :
Energy balances necessitate energy requirements and sources to be expressed in commensurate units¿usually heat. If these balances are complete, the flow of energy through the economy can be traced in such units, and the transformation functions of one form or source of energy to another can be specified. Thus, energy balances permit analysis of the entire energy sector on a whole, rather than on a commodity by commodity, basis. As such, they are capable of being used analytically to solve a number of problems that would otherwise be beyond comprehensive analysis. In this article, four such analytical uses are described and applied.