This module is the third in a series of eleven modules in an energy conservation curriculum for secondary and postsecondary vocational students. It is designed for use by itself or as part of a sequence of four modules on understanding utilities (see also modules 5-7). The objective of this module is to introduce the student to utility bills used for residential and commercial customers. First, an introduction to the module and definitions of key terms are provided. Next, the text is presented in the following five units: (1) electric meters; (2) electric rates; (3) the electric bill; (4) gas meters and gas rates; and (5) the gas bill. The information in each unit is presented in lecture format accompanied by laboratory exercises and questions/examples for class discussion. A bibliography and several charts illustrating the text material are found at the end of the module. (BM)