Mini-power plant

While coal is the major fuel for electric power in the United States, natural gas is the fastest growing fuel (Speight, 2007a,b, 2008) and the importance of coal to electricity generation worldwide is set to continue, with coal fueling 44% of global electricity in 2030. Natural gas is also likely to be a primary fuel for distributed power generators— mini-power plants that would be sited close to where the electricity is needed. 

Often, the mini-power plants do not come as a separate unit or module but are integrated into the devices powered by them and share their housing. This, however, interferes considerably with the easy communication of the fuel cell, with the ambient atmosphere supplying its oxygen needs and serving as a heat and product sink. 

A power plant with mini-fuel cells comprises both the fuel battery itself with all peripherals and the containers with the reactant (fuel). The weight of the battery together with the ancillary equipment, Gbat-i-anc, to a first approximation is proportional to the electric power, Pg, generated that is, Gbat-i-anc = otPe. The... 

Mini-fuel cells and mobile fuel cells have some specific features. One of the most important jobs of ordinary (large-sized) fuel cells is the highly efficient conversion of chemical fuel energy to electrical energy. For higher fuel utilization efficiency, power plants involving such fuel cells include many peripherals to monitor and regulate the rate of the fuel supply, as weU as external parameters such as temperature and pressure that influence this efficiency. 

The major emphasis will be on the minimum variance stochastic control schemes of Box and Jenkins ( b) and Astrom (l ), and on modifications of them. These schemes have seen successful application in the polymer industry, and they are intuitively appealing and yet simple enough to be implemented by the plant operators using either a programmable hand calculator or control charts and tables. More powerful adaptive versions can be implemented if a small online mini-computer is available. 

Used as a mini-pilot-reactor, the bench-scale-calorimeter in many cases provides data which permits a direct scale-up to plant scale, when conventional means would neccessite a pilot stage. Thus, it is a powerful tool for process development, drastically reducing cost and time required. 

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