Application of cooling, heating, and power (CHP) for office buildings was evaluated based on a nondimensional analysis of energy cost and primary energy consumption. Two CHP scenarios for a hypothetical office building in three different geographical locations were considered. Gas-fired micro-turbine generators were utilized in all cases to provide on-line electricity and thermal energy for the building systems. One of the scenarios aimed at maximum conservation of fossil fuel and emission reduction by incorporating thermally activated cooling and heating systems. The other scenario was primarily intended to provide the required electrical energy of the building independently of the local electric utility. Both scenarios were compared with the baseline system that incorporated electric cooling and gas-fired heating systems utiliz-ing the local utilities. As a prerequisite for energy and energy cost analysis, the electricity and gas consumption profiles of the building were evaluated for the cases considered using a simulation program. In this study, the total annual energy cost for each case was expressed as a function of a dimensionless electricity-to-fuel cost ratio and was normalized with respect to the corre-sponding energy cost for the baseline system. These features facilitated a what if" energy cost analysis encompassing a wide range of electricity cost relative to that of natural gas. For each case representing a combination of the CHP arrangement and location, the variation of the annual energy cost with respect to electricity-to-gas cost ratio was presented, and the breakeven point was determined and discussed. The potential of each scenario in conservation of fossil fuel was quantified by evaluating the primary energy consumption for all cases considered. The effect of power generator efficiency on the total primary energy consumption and cost was examined as well. "