Efficiencies of cases 5-8 in summer

Summer Hydrogen input Hydrogen input Usable energy efficiency Used energy efficiency Usable energy efficiency Used energy efficiency 

Summer Almost all electrical energy of the fuel cell is used and about 92-93 % of thermal energy remains (Table VI.5). Efficiency of usable energy for I. law of thermodynamics is 76.8 % and for II. law of thermodynamics is 52.65 % which are same as cases 1-4. Usable energy efficiencies are nearly same but case-3 has maximum usable energy efficiencies according to thermodynamics first and second law and efficiency values are 40.65 % and 45.11 %, respectively (Table VI.6). 

Winter There are four scenarios to compensate energy requirement of the residential. 

Scenario I In this scenario, space heating is compensated by heat pump and thermal energy of fuel cell. Almost all thermal energy is consumed as shown in the Table VI.7. Usable energy efficiencies are 74.39 % for I. law and 52.2 % for II. law. Surplus electrical energy efficiencies from case-5 to case-8 are 48.62 %, 66.44 %, 60.48 % and 53 %, respectively (Table VI.7). Maximum used energy efficiencies are at case-5 where minimum unused electrical energy and values are 55.35 % for I. law and 29.99 % for n. law of thermodynamics (Table VI.8). 

Summer Space cooling Water heating Electric cons. Fuel cell run time Total Unused energy Usage of Usage of Surplus  

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