Two similarly large buildings and air conditioning systems are comparatively analyzed as to energy consumption, costs, and inefficiency during certain measured periods of time. Building design and velocity systems are compared to heating, cooling, lighting and distribution capabilities. Energy requirements for pumps, fans and lighting are found to be the major contributors to operating costs. This analysis suggests a method of obtaining reliable estimates of energy consumption and costs so architects and clients may become aware of the implications of their environmental control and design decisions. Charts and graphs are used to analyze the problem; a reference list is supplied. (TG)