Energy-saving effect of a residential polymer electrolyte fuel cell cogeneration system combined with a plug-in hybrid electric vehicle

• Published in: Energy conversion and management 2014-01, Vol.77, p.40-51
• Main Authors: Wakui, Tetsuya, Wada, Naohiro, Yokoyama, Ryohei
• Format: Article
• Language: English
• Subjects: Applied sciences; Charging; Cogeneration; Combined power plants; Electrolytes; Energy; Energy saving; Energy use; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Hybrid vehicles; Installations for energy generation and conversion: thermal and electrical energy; Operational planning; Optimization; Plug-in hybrid electric vehicle; Polymer electrolyte fuel cell; Residential energy
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2013.09.018

•Combined use of PEFC-CGS and PHEV is focused on for energy savings.•Optimal operational planning considering daily start–stop operation is modeled.•Charging PHEV with PEFC-CGS increases electric capacity factor of PEFC-CGS.•Combined use has higher energy-saving effect than their separate use.•Combined use synergistically saves energies in residential and transport sectors. The energy-saving effect of a residential polymer electrolyte fuel cell cogeneration system (PEFC-CGS) that adopts a daily start–stop operation with no reverse power flow, combined with a plug-in hybrid electric vehicle (PHEV) is analyzed by optimal operational planning model based on mixed-integer linear programming. This combined use aims to increase the electric capacity factor of the PEFC-CGS by charging the PHEV using the PEFC-CGS output late at night, and targets the application in regions where the reverse power flow from residential cogeneration systems to commercial electric power systems is not permitted, like in Japan. First, the optimal operational planning model that incorporates the daily start–stop operation of the PEFC-CGS is developed. The energy-saving effect of the combined use of the PEFC-CGS and PHEV is then analyzed on the basis of observations of the optimal operation patterns for a 0.75-kWe PEFC-CGS, a simulated energy demand with a sampling time of 5min, and various daily running distances of the PHEV. The results show that the combined use of the PEFC-CGS and PHEV increases the electric capacity factor and hot water supply rate of the PEFC-CGS and saves more energy in comparison with their separate use in which the PEFC-CGS is used but the PHEV is charged only using purchased electric power. Consequently, this feasibility study reveals that the combined use of the PEFC-CGS and PHEV provides the synergistic effect on energy savings in the residential and transport sectors.