Fuel SOFC

Canada also reports industry capabilities in the production of 5-20 kW SOFCs. Residential and commercial applications are being demonstrated in Europe, the US and in cold weather climates including Alaska. Canada s research efforts are focused on developing "noval-nano" based materials and noval architecture to enable lower temperature, direct fuel, SOFC operation. 

The German industry is pursuing the design of a natural gas fueled SOFC with a self-supporting structure of an electrolyte of 100 fim thickness and an area of 50 by 50 mm. Developmental steps of SOFC in the Siemens company have started with a 50 W unit in 1993, passed 370 W, 1.8 kW, 10.8 kW, and eventually reached 20 kW in 1996. The design specifications of a SOFC combined heat power plant (see Fig. 7-5) are an efficiency of > 50 %, a fuel utilization of > 90 %, a thermal cyclability of > 100 cycles, and an operational lifetime of > 40,000 hours. A 20 % pre-reforming of the natural gas fuel is required. Its construction is expected within the next 2-3 years [40]. 

Attention has also been given to Cu-based anode, due to its lower catalytic activity for C-C bond formation, thus suppressing the deposition of carbon on cermet anodes of hydrocarbon-fueled SOFCs [34]. Cu is... 

In the first years of work on perovskite proton conductors, many researchers, including the author, assumed that PCFCs would be useful only in coimection with hydrogen fuel cells, while with hydrocarbon fuels, SOFCs would be the only choice. However, work by Coors and coworkers has demonstrated that perovskite proton conductors with minority oxide ion conduction can sustain stable currents for long... 

Kim T et al (2006) A study of carbon formation and prevention in hydrocarbon-fueled SOFC. J Power Sources 155 231... 

In order to avoid carbon deposition, the steam-to-carbon ratio is normally higher than 2 (Ni, 2012). However, a high steam concentration could decrease the SOFC s performance. A common practice for methane fueled SOFCs is to pre-reform methane fuel to obtain a gas mixture with sufficient hydrogen concentration. In this chapter, a commonly used 30% pre-reformed methane fuel mixture is employed (Ni and Leung, 2008). In operation, the fuel mixture is fed to the anode micro-channel while air is supplied to the cathode micro-channel. MSR and WGSR occur in the porous anode, as shown in Equations (6.1) and (6.2), respectively ... 

With currently built and tested devices, the most widely used material for the electrolyte is YSZ. Therefore this material has been chosen to study bio-fuel fueled SOFC. Achievable levels of fuel utilization factor in cells used commercially reach 80%. Other cell parameters were fixed as follows electrolyte thickness of 15 pm, maximum current density (/max) of 2.6 A/cm, cell working temperature of 800°C, and cell pressure at atmospheric pressure. During the analysis of the oxidant, flow was kept at a constant excess air factor (2) of 3. 

Chapter 223. Rare-earth Materials for Solid Oxide Fuels (SOFC) by Natsuko Sakai, Katsuhiko Yamaji, Tenihisa Horita, Yue Piug Xioug and Harumi Yokokawa... 

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