chapter 4 Fuel cell applications chapter 4 Fuel
- Slides: 52
chapter 4. Fuel cell applications
chapter 4. Fuel cell applications • • 4. 1 4. 2 4. 3 4. 4 Portable Power Application Backup Power Application Transportation Application Stationary Power Application
chapter 4. Fuel cell applications 4. 1 Portable Power Application • Table 4 -1 Example of Portable Fuel cell
chapter 4. Fuel cell applications 4. 1 Portable Power Application • Example of Portable Fuel cell
chapter 4. Fuel cell applications 4. 2 Backup Power Application • Table 4 -2 Example of Commercial Backup Power fuel cells
chapter 4. Fuel cell applications 4. 2 Backup Power Application • 4. 2. 1 Basic electrolyzer calculation • The required electrolyzer power PFC = Fuel cell nominal power (k. W). τFC, τEL = Duration of operation in the fuel cell and electrolyzer modes, respectively (hours). CFFC, CFEL = The capacity factors of fuel cell and electrolyzer defined as a ratio between average and nominal power. ηFC, ηEL = The system efficiency of the fuel cell and the electrolyzer.
chapter 4. Fuel cell applications 4. 2 Backup Power Application • 4. 2. 1 Basic electrolyzer calculation • The electrolyzer efficiency Vel_cell = The electrolyzer cell voltage i el = The electrolyzer current density (Acm-²) i loss = The current and hydrogen loss (Acm-²)
chapter 4. Fuel cell applications 4. 2 Backup Power Application • 4. 2. 1 Basic electrolyzer calculation • The electrolyzer system efficiency ηDC= The efficiency of power conversion (AC/DC or DC/DC). ζ= The ratio between parasitic power and net power consumed by the electrolyzer.
chapter 4. Fuel cell applications 4. 2 Backup Power Application • 4. 2. 1 Basic electrolyzer calculation • . . Pbi= The initial H₂ pressure in the bottle n. H 2= Moles of hydrogen m. H 2= The molecular weight of hydrogen Z= The compressibility factor of hydrogen Tb= The bottle temperature Vb=The bottle volume
chapter 4. Fuel cell applications 4. 3 Transportation Application • • 4. 3. 1 4. 3. 2 4. 3. 3 4. 3. 4 Automobiles Buses Utility vehicles Scooters and bicycles
chapter 4. Fuel cell applications 4. 3 Transportation Application Characteristics of Fuel Cell for Transportation Application • A fuel cell is sized to provide all of the power to a vehicle. A battery may be present for startup. • A fuel cell typically supplies a constant amount of power, so for vehicle acceleration and other power spikes, additional devices are typically switched on such as batteries, ultra or supercapacitors, and so on. • Sometimes a fuel cell is used as the secondary power source. A system is set up where batteries power the vehicle, and the fuel cell just recharge the batteries when needed. • A fuel cell can run part or all of the vehicle’s electrical system. Sometimes another engine is used for propulsion.
chapter 4. Fuel cell applications 4. 3 Transportation Application Issues in Fuel Cell for Transportation Application • Current manufacturing methods for the mass producion of fuel cells are cost prohibitive. New techniques, mass fabrication methods, and materials need to be created to lower the cost of producing fuel cells. • If fuels other than hydrogen are used, CO poisoning of the catalyst may become an issue. The catalyst may need to be replaced or refreshed over time. • The size and weight of the fuel tanks. • A robust, efficient fuel cell system that can withstand long-term frequent use.
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles Table 4 -3 Fuel cell Vehicles by major Manufacturers (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles Table 4 -3 Fuel cell Vehicles by major Manufacturers (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles Table 4 -3 Fuel cell Vehicles by major Manufacturers
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles The efficiency of an automobile engine as specific fuel consumption. LHVfuel=The lower heating value of fuel (k. J/kg) Ηvehicle_sys=The vehicle efficiency
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles • Fig 4 -2 Free body diagram of an automobile on an incline.
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles Total mechanical power mveh= The total mass of the vehicle, θ= The angle of the slope aveh= The acceleration of the vehicle vveh= The velocity of the vehicle CRR= The coefficient of the tire rolling resistance ρair= The density of the air CD= The drag coefficient AF= The frontal area
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles The vehicle fuel economy. fsp_fuel_cons =The specific fuel consumption in gk. Wh⁻¹ Vspeed=The vehicle speed (ms⁻¹).
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles The amount of power output. Pauxiliary = The power needed by auxiliary systems. ηdrivetrain = The efficiency of the electric motor, controller subsystem. Pparasitics = The parasitic power.
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 1 Automobiles The stack specific volume. ncells = The number of cells in a stack dcell = The individual cell thickness including the cooling arrangements (m) dep = The thickness of the end plates αact = The ratio of cell active area and bipolar plate area Vcell = The cell potential at nominal power (V), and i = The current density at nominal power (Acm⁻²)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 2 Buses
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 2 Buses Table 4 -4 Fuel cell buses Demonstrated date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 2 Buses Table 4 -4 Fuel cell buses Demonstrated date
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 3 Utility vehicles Table 4 -5 Utility Vehicles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 3 Utility vehicles Table 4 -5 Utility Vehicles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 3 Utility vehicles Table 4 -5 Utility Vehicles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 3 Utility vehicles Table 4 -5 Utility Vehicles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 3 Utility vehicles Table 4 -5 Utility Vehicles Demonstrated to Date
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 4 Scooters and bicycles Table 4 -6 Scooters and Bicycles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 4 Scooters and bicycles
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 4 Scooters and bicycles Table 4 -6 Scooters and Bicycles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 4 Scooters and bicycles Table 4 -6 Scooters and Bicycles Demonstrated to Date (continued)
chapter 4. Fuel cell applications 4. 3 Transportation Application • 4. 3. 4 Scooters and bicycles Table 4 -6 Scooters and Bicycles Demonstrated to Date
chapter 4. Fuel cell applications 4. 4 Stationary Power Application Table 4 -7 Stationary power system Demonstrated to data (continued)
chapter 4. Fuel cell applications 4. 4 Stationary Power Application Table 4 -7 Stationary power system Demonstrated to data (continued)
chapter 4. Fuel cell applications 4. 4 Stationary Power Application Table 4 -7 Stationary power system Demonstrated to data (continued)
chapter 4. Fuel cell applications 4. 4 Stationary Power Application Table 4 -7 Stationary power system Demonstrated to data (continued)
chapter 4. Fuel cell applications 4. 4 Stationary Power Application Table 4 -7 Stationary power system Demonstrated to data
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Basic stationary fuel cell calculation. Pnet = The usable power amounts. Qnet =The usable heat amounts. ηfuel =The amount of fuel input into the fuel cell system. • The total efficiency of the fuel cell system
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Basic stationary fuel cell calculation. The electrical efficiency of the stationary fuel system PAC = The usable AC power generated Paux_equipment = The power required by auxiliary equipment Pcompressor =The power required by compressor Ppump =The power required by the pump Pcontrol =The power required by the control system
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Basic stationary fuel cell calculation. • The thermal efficiency of the stationary fuel cell system • The stationary fuel cell system uses a fuel processor, the efficiency of the fuel processor • The DC/AC efficiency of the stationary fuel cell system
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Basic stationary fuel cell calculation. • For any auxiliary equipment used, the efficiency • The efficiency of the fuel cell stack
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The eqn for simple payback time Pfc, norm = The fuel cell power system nominal power Cfc =The specific cost of fuel cell power system per k. W of nominal power AEP=The annual electricity produced by the fuel cell power system per k. W of nominal power COE=The cost of electricity ηfc = The average annual efficiency of the fuel cell system, Cng =The cost of natural gas using the lower heating value of natural gas
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The amount of electricity produced (k. W)annually (AEP) by a fuel cell system. Pfc_time =The fuel cell power at a given time. hyear-operating =The yearly operating hours of fuel cell. • The amount of electricity produced annually (in k. W) CF =The capacity factor
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The average annual efficiency Pfc and ηfc = The fuel cell system power output and system efficiency.
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. Cf =The fuel cost Cfix = The costs associated with the fuel cell installation excluding the costs of individual cells, but including the balance of plant and installation costs Ccell = The cost of each individual cell Ncell = The number of individual cells PFC = The power output of the fuel cell in kilowatts Vcell = The cell nominal voltage Acell = The cell active area
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The capital recovery factor ir = The annual interest rate (in percent) L= The lifetime of the individual cells (in years). • The capital recovery cost Crep= The replacement cost of the fuel cell at end of lifetime
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The cost of electricity produced by a fuel cell Senv =Only used with fuel cell types that use hydrogen from non-fossil fuel based sources as the fuel, and can be defined as follows. Cp=The environmental damage cost δ=The ratio of hydrogen utilization efficiency to that of fossil fuels ε=The ratio of environmental impact of hydrogen utilization to that of fossil fuels
chapter 4. Fuel cell applications 4. 4 Stationary Power Application • Economics of stationary fuel cell system. • The simple payback time AEPint = The amount of electricity consumed internally (k. Wyhr⁻¹), AEPexp = The amount of electricity exported back to the grid (k. Wyhr⁻¹) COEexp = The price of electricity exported back to the grid (k. Wyhr⁻¹).
chapter 4. Fuel cell applications Chapter Summary • Certain fuel cell types are better suited for small portable technologies, backup power, automobiles, or stationary power applications. Fuel cells for each of these applications have been demonstrated, and there are some fuel cells commercially available in these categories. The fuel cell design parameters such as power output, heat balance, efficiency, size, weight, and fuel supply may be slightly different for each application, and must be customized to suit the required load.