Several popular textbooks are in common use in senior technical elective HVAC courses offered in mechanical engineering. These texts, almost without exception, concentrate on the design load calculations as outlined in theASHRAE Handbook-Fundamentalsor in theLoad Calculation Manual. The subject of energy analysis is usually given only cursory attention at the end of the cooling load chapter. This paper outlines a simplified, hour-by-hour, single-zone energy analysis that incorporates many of the major features of more complex programs yet can be performed on the more powerful microcomputers that are often available to students. While the simplicity of the program prevents it from being used seriously on a commercial basis, it does illustrate thermal lag effects, the dominance of solar radiation on cooling loads, and the impact of outdoor air conditions on total equipment load. This program can easily illustrate the impact of glazing, insulation, infiltration, and outdoor air makeup on weekly cooling costs.Units: I-P