Power plants using fuel cells

Power plants using fuel cells can now take the place of the present polluting coal or oil-based (indirect) electricity-producing plants. However, in a further development, it would be possible to extract COz from the atmosphere, and H2 from solar-driven electrolysis, to produce methanol with zero net injection of C02 into the atmosphere. These plants would at first ran on hydrogen from these fossil fuels, the attraction being the reduction of pollution and the increase in the conversion efficiency. To what extent the latter two commodities would be supplied from remote sites, or collected onsite at... 

Properly designed fuel cells may be as much as 70 percent efficient, about twice as efficient as an internal combustion engine. In addition, fuel-cell generators are free of the noise, vibration, heat transfer, thermal pollution, and other problems normally associated with conventional power plants. Nevertheless, fuel cells are not yet in widespread use. A major problem lies in the lack of cheap electrocatalysts able to function efficiently for long periods of time without contamination. The most successful application of fnel cells to date has been in space vehicles (Figure 19.12). 

Fhosphoric acid does not have all the properties of an ideal fuel cell electrolyte. Because it is chemically stable, relatively nonvolatile at temperatures above 200 C, and rejects carbon dioxide, it is useful in electric utility fuel cell power plants that use fuel cell waste heat to raise steam for reforming natural gas and liquid fuels. Although phosphoric acid is the only common acid combining the above properties, it does exhibit a deleterious effect on air electrode kinetics when compared with other electrolytes ( ) including such materials as sulfuric and perchloric acids, whose chemical instability at T > 120 C render them unsuitable for utility fuel cell use. In the second part of this paper, we will review progress towards the development of new acid electrolytes for fuel cells. 

The fuel processor efficiency is size dependent therefore, small fuel cell power plants using externally reformed hydrocarbon fuels would have a lower overall system efficiency. 

Hybrid power plants using high temperature fuel cells, and capture of CO2 from cathode off-gas. 

The chapter is organized as follows. In Section 2, general principles of MCFC-microturbine hybrid power cycles are explained. In Section 3, robust control for fuel cell-microturbine hybrid power plant using biomass is introduced. Section 4 presents the modeling of SOFC plants on the distribution system using identification algorithms. Effect of a SOFC plant on distribution system stability is discussed in Section 5, and finally, conclusions are provided in Section 6. 

Robust Control for Fuel Cell-Microturbine Hybrid Power Plant Using Biomass... 

Energy recuperation from undesired hydrogen using fuel cells enables higher efficiency than in conventional thermal power stations. This is successfully tested in an industrial scale the biggest plant has 1 MW electrical power [3]. 

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