Fuel-cell-based cogeneration systems are very attractive because of their high electrical efficiency and low emissions of air pollutants. The polymer electrode membrane fuel cell (PEMFC) is especially appropriate for distributed power generation applications because it can be operated at relatively low temperatures and the system is less sensitive to the CO2 produced during the fuel reforming process. In this study, the optimal operating condition were determined for a 1-kW PEMFC-based combined heat and power (CHP) system based on the daily electricity and heat demand patterns for an apartment house in Korea, whose average monthly electricity and heat demands are 472 kWh and 1312 kWh, respectively. In addition, the unit cost of electricity was estimated using a thermoeconomic analysis and the economic gain achieved by introducing the PEMFC-based CHP system in the apartment house was calculated. Approximately 20% savings can be achieved in the operational cost of the PEMFC-based CHP system, if the installation cost is supported by the government. (C) 2012 Elsevier Ltd. All rights reserved.