@article{oai:kitami-it.repo.nii.ac.jp:00008233, author = {Abeer, Galal El-Sayed and OBARA, Shin'ya}, issue = {2}, journal = {Journal of Power and Energy Systems}, month = {}, note = {In this study, the combined system of a solid-oxide fuel cell (SOFC) and a proton-exchange membrane fuel cell (PEFC) is developed. The proposed system consists of a SOFC-PEFC combined system and a photovoltaic system (PV) as the energy supply to a micro-grid. The exhaust heat of the SOFC is used for the steam reforming of the bio-ethanol gas with time shift utilization of the exhaust heat of the SOFC in optional time. The SOFC-PEFC combined system with the PV was introduced in a micro-grid of 30 residences in Sapporo, Japan. The operation plan of the system has three cases: without solar power, with 50% and with 100% of solar output power. Moreover, three types of system operation of using the SOFC independent operation, PEFC independent operation and SOFC-PEFC combined system are used to supply the demand side. A comparative study between the types of system operation is presented. The power generation efficiency is investigated for different load patterns: average load pattern, compressed load pattern and extended load pattern. This paper reported that the power generation efficiencies of the proposedsystem in consideration of these load patterns are 27% to 48%.}, pages = {274--289}, title = {Power Generation Efficiency of Photovoltaics and a SOFC-PEFC Combined Micro-grid with Time Shift Utilization of the SOFC Exhaust Heat}, volume = {4}, year = {2010} }