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To improve the mechanical properties of proton exchange membranes, consequently improving the performance of direct borohydride fuel cells, the present study prepared sulfonated chitosan-g-sulfonated polyvinyl alcohol/polyethylene oxide doped with sulfated zirconia composite (SCS-g-SPVA/PEO/SZrO2) polyelectrolyte membranes. Two fabrication techniques were followed, solution casting and electrospinning, to have the membranes in film and fiber forms and study the effect of the different forms on the membrane’s physicochemical properties. For the casting technique, different concentrations of SZrO2 (1-3 wt%) were used, while the optimum concentration of SZrO2 (3 wt%) was used in the electrospun one (SCS-g-SPVA/PEO/SZrO2-CF). SCS-g-SPVA/PEO/SZrO2-C membranes were prepared in a single step. The grafting and the crosslinking were carried out using glutaraldehyde and sulfosuccinic acid as sulfonating agents for chitosan and PVA and coupling agents simultaneously using click chemistry. On the other hand, SCS-g-SPVA/PEO/SZrO2-CF membranes were prepared in two steps. They were fabricated with electrospinning and then dipped into the coupling and crosslinking solutions. The casting membranes’ physicochemical properties were improved by increasing the SZrO2 content. The experimental results further show that the fabrication procedure significantly influences the physicochemical properties of the membranes. For instance, the composite fiber membrane demonstrated higher selectivity and higher ion exchange capacity (IEC) than the casting membrane. Furthermore, by using the response surface methodology model, the effects of ion exchange capacity, water uptake, and oxidative stability were optimized as three independent variables that affected the ionic conductivity of SCS-g-SPVA/PEO/SZrO2-3C. The optimized ionic conductivity of the SCS-g-SPVA/PEO/SZrO2-3C membrane was 13.6 mS cm−1, achieved at the maximum point of the polynomial model, with an IEC of 0.74 meq g−1, ∼92% water uptake, and about 93% oxidative stability.

The operation and economics of 1-shift and 2-shift electric taxis in Ottawa, ON, Canada, were evaluated in a simulation study using real-world driving data from gasoline taxis and detailed battery life modelling. Electric taxis were able to operate like gasoline taxis on most days and showed favourable economics. Without any incentives, 1-shift taxis in Ottawa can provide significant net savings of almost $20,000 over a 6-year life, requiring only limited adjustments to driver behaviour. Similar or greater savings can potentially be created by 2-shift taxis, depending on battery longevity, availability of charging infrastructure and recharging frequency

Local generated and distributed system for thermal and electrical energy is sighted in the near future to reduce transmission losses instead of the centralized system. Distributed Energy Resources (DER) is designed at different sizes (small and medium) and it is incorporated in energy distribution between the hubs. The energy generated from each technology at each hub should meet the local energy demands. Economic and environmental enhancement can be achieved when there are interaction and energy exchange between the hubs. Network energy system and CO2 optimization between different six hubs presented Canadian community level are investigated in this study. Three different scenarios of technology systems are studied to meet both thermal and electrical demand loads for the six hubs. The conventional system is used as the first technology system and a reference case study. The conventional system includes boiler to provide the thermal energy, but the electrical energy is imported from the utility grid. The second technology system includes combined heat and power (CHP) system to meet the thermal demand loads and part of the electrical demand load. The third scenario has integration systems of CHP and Organic Rankine Cycle (ORC) where the thermal waste energy from the CHP system is used by ORC to generate electricity. General Algebraic Modeling System (GAMS) is used to model DER system optimization based on energy economics and CO2 emission analyses. The results are compared with the conventional energy system. The results show that scenarios 2 and 3 provide an annual total cost saving of 21.3% and 32.3 %, respectively compared to the conventional system (scenario 1). Additionally, Scenario 3 (CHP & ORC systems) provides 32.5% saving in CO2 emission compared to conventional system subsequent case 2 (CHP system) with a value of 9.3%.&nbsp