Efficiencies of cases 5-8 in winter for scenario IV

Winter (IV) Hydrogen input Hydrogen input Usable energy efficiency Used energy efficiency Usable energy efficiency Used energy efficiency 

Space heating is supplied by WGHIOO model of heat pump according to winter condition as case-1. However, unlike case-1, domestic water heating is supplied by electrical energy of fuel cell. Consequently, thermal energy is not used in this case and all electrical energy of fuel cell is consumed. 

Winter The results are shown in tables VI. 15 and VI. 16. Production of 97.52 kWh heat per day is not used. Usable energy efficiencies are 74.39 % for I. law and 52.20 % for II. law of thermodynamics as at cases 1-4. Used energy efficiencies are 38.26 % and 45.50 % for I. law and II. law of thermodynamics, respectively. These efficiency values are lower than at case-1. 

Winter There are four scenarios for case-10. The results are shown in tables VI. 15 and VI. 16. 

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