Cooling fuel cells

In a typical PAFC system, methane passes through a reformer with steam from the coolant loop of the water-cooled fuel cell. Heat for the reforming reaction is generated by combusting the depleted fuel. The reformed natural gas contains typically 60 percent H9, 20 percent CO, and 20 percent H9O. Because the platinum catalyst in the PAFC can tolerate only about 0.5 percent CO, this fuel mixture is passed through a water gas shift reactor before being fed to the fuel cell. 

Cooling Fuel Cells Industry and Business, Energy as a Factor of Production in Turbines, Gas Turbines, Steam. 

The Peugeot Quark ATV uses an air-cooled fuel cell with a 40 cell nickel metal hydride battery. The 9 liter hydrogen tank can be pressurized to 10,150 psi for a range of up to 80 miles. The tank is designed to be exchanged for a full one when empty. Each 17 inch wheel has its own electric motor that can produce 74 pound-feet of torque. The motors also supply regenerative braking. 

J.M. Feret, "Gas Cooled Fuel Cell Systems Technology Development," Final Report, NASA CR-175047, prepared by Westinghouse Electric Corp. under Contract No. DEN 3-290 for NASA Lewis Research Center, August 1985. 

Gas Cooled Fuel Cell Systems Technology Development," Westinghouse/DOE, WAES-TR-92-001, March 1992. 

Key Characteristics of a 5 kW Liquid-Cooled Fuel Cell System... 

Ruge M and Hoekel M (2005), Air-Cooled Fuel Cell Stack Made of Foil Materials, 3rd European PEFC Forum, Lucerne File No. B096. 

The fuel cell must be cooled with either water or air, and the heat can be converted to electricity in a bottoming cycle. The dc electrical output ot the stack is usually converted to ac and stepped up or down in voltage, depending on the application. Analogous to PAFds, M(iF(i stacks are about 1 nr (10.8 ft") in plan area and quite tall. A stack generates 200 to 300 kW. Market entiy is expected in 1999. 

Because of these losses, fuel cells generate significant heat, and this places a limit on the maximum power available because it is very difficult to provide adequate cooling to avoid formation of potentially... 

Cooling strongly depends on fuel cell operating temperature and also depends on the fuel cell s external environment. For low temperature fuel cells, cooling imposes a significant energy debit because pumps need to force coolant out to a heat... 

A fuel cell system also needs ancillaries to support the stack, just as an IC engine has many of the same type of ancillary subsystems. Major subsystems are needed for providing adequate humidification and cooling, and for supplying fuel and oxidant (air) with the correct purity and appropriate c uantity. 

ISPP imits are not the only micro device imits of interest for space applications micro fuel cells, compact cleanup units for water treatment, portable heating and cooling units and devices for chemical processing and mining are considered [91]. 

Initial systems will be less than 20 MW, with typical system sizes of 1 to 10 MW. Future systems, in the megawatt class size, will boost efficiency even further by combining two solid oxide fuel cell modules with more advanced gas turbines and introducing sophisticated cooling and heating procedures. 

Fuel cell vehicles, 73 800-801 Fuel cell voltage equation, 72 208 Fuel cell voltages, 72 206-209 versus current densities, 72 208 Fuel cooling, in pressurized water reactors, 77 544... 

The waste heat the fuel cell generates can be used in a cogeneration process to provide services like heating, cooling, and dehumidification. Instead of the 50% efficiency of a fuel cell with a reformer, or 60-70% without one, 90% or better is possible for the total system efficiency. 

In Ballard s alliance with Ford, Volvo, and Daimler Chrysler, they will supply the other components of the vehicles from the car body to the electric motor drive. The fuel cell will function as the car s engine. It needs cooling, control and fuel processing. 

The costs of a PEMFC stack are composed of the costs of the membrane, electrode, bipolar plates, platinum catalysts, peripheral materials and the costs of assembly. For the fuel-cell vehicle, the costs of the electric drive (converter, electric motor, inverter, hydrogen and air pressurisation, control electronics, cooling systems, etc.) and the hydrogen storage system have to be added. Current costs of PEM fuel-cell stacks are around 2000/kW, largely dominated by the costs of the bipolar plates and... 

Portable fuel-cell systems are systems that produce electricity for devices with a performance ranging from several watts to 10 kilowatts. The heat produced in the process is a by-product that is normally not used. The system has, therefore, to be cooled down by fans or cooling surfaces, etc. A wide range of applications is possible for fuel cells from small electronic devices like camcorders, mobile phones, laptops, etc. to electric tools, back-up systems, or power generation on boats or caravans. 

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