Utility-stationary application

Utility-Stationary Applications. Fuel cell and hydrogen energy technologies can be complementary over the full spectrum... 

The Shell studies imply that fuel cell sales will start with stationary applications to businesses that are willing to pay a premium to ensure highly reliable power without utility voltage fluctuations or outages. This demand helps to push fuel cell system costs below 500 per kW, providing the era of transportation which drives costs to 50 per kilowatt. But, can the high-reliability power market really drive transportation fuel cell demand and cost reductions, especially for proton- exchange membrane (PEM) fuel cells ... 

It is clear that a broad mass market is not expected until after 2010 (Gummert and Suttor, 2006). But there are already a number of pilot and demonstration systems installed worldwide. It is very difficult to obtain a complete overview of installations because, on the one hand, the data are published by different players, such as utilities, manufacturers or users for their own fuel cells and, on the other hand, if an installation does not work, no data are published or sometimes the system is shut down. Nevertheless, Fuel Cells 2000 have set up a fuel cell database for stationary applications. Most entries are from the USA, but it should be pointed out that Japan installed 480 stationary plants in 2005 alone (Fuel Cell Development Information Centre, personal communication, 2006). 

MW installations. Recently there are also major efforts and some initial success in implementation of rechargeable lithium-ion technology for stationary applications. From the view point of global energy utilization and consumption, the ultimate goal for stationary batteries is power-line load leveling. 

Another, exploratory version of the Na-S system (aimed at present at stationary applications) is under development at Dow Chemical Company. It operates at 300°C and utilizes hollow sodium borate glass fibers as electrolyte in the form of thousands of thin hollow fibers sealed at one end and open at the other to a common reservoir of molten sodium. The fibers are wrapped in Mo-coated aluminum foil which serves as a positive electrode for the polysulfide melt, which fills the space between the fiber wall and the Al. 

Lead-acid batteries were first used in stationary, stand-by applications more than 130 years ago [1]. For a long period of time, only flooded lead-acid batteries were used. Nowadays, UPS and telecommunications applications use valve-regulated batteries. Large, utility-scale applications such as load levelling continue to use flooded batteries, but it seems that, increasingly, valve-regulated batteries are chosen even for these applications. 

Depending on the application, the flow of air may be directed in different ways to obtain specific effects. In such drum film coaters some or all of the panels are double walled and perforated to allow air inlet and exhaust in a controlled manner [ B.48, B.97]. Another design utilizes stationary, hollow, perforated paddles that are immersed in the product and create an unidirectional, constant, and homogeneous flow of air in the tumbling particle bed. Similar to what has been achieved with double walled, perforated and segmented panels in polygonal drums, in cylindrical drums using paddles, air can be directed in different ways, too (Fig. 6.2-79). 

Different types of catalytic systems have been considered for use in the SCR reaction for stationary applications, including noble metals, metal oxides and zeolites. Among these categories, metal oxide based catalysts are the most commonly utilized SCR systems nowadays. 

Africa)io is a variant of sodium-sulfur technology where sulfur is replaced with a metal chloride such as NiCl2 (nickel chloride) or FeCU. It was specifically developed for applications in electric vehicles, freight transport and public transport the ZEBRA battery is more particularly intended to serve buses and utility vehicles. As with the Na-S battery, the vibrations felt in a vehicle may cause premature aging of the ceramic/metal interface. Today, such batteries are also being considered for stationary applications. 

From the mid-1990s, there arose anew wave in fuel cell applications, that is, the automotive application and closely related applications of small stationary. It began with PEFC. Even so, SOFC has also received the impacts of new applications. This leads to two important efforts on SOFC developments (1) severer requirements for mechanical stability in automotive applications [22] and (2) smaller stationary application. The former has come from the new application proposed by BMW, Delphi, and Renault to utilize SOFC systems as auxiliary power unit in combustion engine cars. Since BMW and Delphi have cooperated with National Laboratories in their own countries, materials development has been made to improve mechanical instability. Development of simulation technique also helps to improve the stack technologies. The latter case of the small stationary systems gave rise to a big impact in Japan, Australia, Switzerland, and UK where the SOFC cogeneration systems have attracted strong attention. 

Although some SOFC applications require systems no larger than the 2 to 10 kW to which many tubular and planar SOFC have been scaled-up, most stationary applications, especially those with the greatest potential impact on global energy use, will require systems ranging from about 200 kW for medium-scale distributed generation to several hundred MW for utility-scale power stations. Table 7-5 lists the major SOFC system manufacturers worldwide this list does not include research institutes, universities, and manufacturers of solely ceramic components (1). 

The performanee and durability of a membrane electrode assembly (MEA) is affected signifieantly by the eathode eleetrode eomposition and structure, due to the poor kineties of oxygen reduetion and reaetant transport limitations. Utilization and stability of platinum or its alloys in the PEMFC play important roles in fuel cell efficiency, durability, and the drive for eost reduction through reduced Pt loadings. Cathode catalyst layer degradation is a critical issue for fuel cell durability to meet the requirement of > 5000 hours for automotive applications and > 40,000 for stationary applications. 

Molten carbonate fuel cells can use hydrogen, carbon monoxide, natural gas, propane, landfill gas, marine diesel, and coal gasification products as the fuel. MCFCs producing 10 kW to 2 MW MCFCs have been tested with a variety of fuels and are primarily targeted to electric utility applications. MCFCs for stationary applications have been successfully demonstrated in several locations throughout the world. 

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