Residential fuel cells Japan

SOFC and PEFC are competing in several stationary markets, with advantages to SOFC technology when reformed hydrocarbon or alcohol fuels are used. PEFC systems however have some distinct advantages in applications where frequent start-stop-cycles and extended periods of standstill are required such as in residential CHP applications. Therefore, more PEFC than SOFC units are ciurently in the field in Japan where market introduction of residential fuel cell systems has already taken place. SOFC systems are in the early phase of deployment. 

Japan is currently the leader when it comes to demonstration and commercialization of residential fuel cell systems. In recent years, the government has led a coordinated approach involving collaboration between several companies to reduce the cost of residential fuel cell systems and market them to consumers in an attractive way. 

Figure 38.7 Japan s strategy for commercialization of residential fuel cells (59).

Research and development activities regarding fuel-cell units for the residential sector can be located all over the world. In Japan, 400 lkW fuel-cell systems were tested in 2005 (see Fig. 13.7). But intense attention is also being paid to these applications in the United States, China and Korea. 

Smaller fuel cells (<20 kW, but more typically <5 kW) are being developed for residential applications, particularly in Japan and Europe. These fuel cells use natural gas as fuel (therefore they are equipped with a reformer). Most often they also enable capture and utilization of waste heat and use it for space and/or hot water heating in combination with a natural gas boiler, resulting in high overall efficiency. 

Fuji Electric Advanced Technology of Japan is working on developing similar sized 1 kW residential PEM fuel cell power units. "Its third generation units have an electrical efficiency of 31%, heat recovery efficiency of 42% and an operating life of 10 000 h whilst its pre-production unit, currently under development, will have an electrical efficiency of 32%, heat recovery efficiency of 42% and a targeted 20 000 h lifetime," notes Adamson (2005). Fuji has run several small demonstrations of its fuel cell systems and hopes to commercialize them by 2008 at 12000-16000 each, but with a goal of 2500-4000 by 2015 (Adamson 2005). 

The PEMFC system has seen such an important development in the last ten years that it would be impossible to describe in few lines the extent of its application. The transport area is surely the most challenging. After fluctuating periods, serious advances have been made on the cost and efficiency levels. Daimler is announcing a well-planned market entry for a fuel cell vehicle in 2014. US and Japanese developers are also ready. Already there are several buses fleet in many European, American and Asian cities. Light portable applications have their niche markets and numerous PEMFC units are already in use for residential applications, most particularly in Japan. In Canada, the first commercial benefits from PEMFC systems have been registered in the three last years. Moreover, the intense research activity on membranes and the opportunities offered by higher operating temperatures and relatively low humidity open an important field of development. 

There are markets where the relatively high cost of fuel cell systems, be it residential or commercial, can be justified on the basis of the additional value associated with green credentials or other benefits. In Japan under the Ene-Farm program subsidies are available for the sale of residential CHP fuel cell systems. 

Toshiba Fuel Cell Power Systems (TFCPS) (Japan) a subsidiary of Toshiba, has the sole purpose of commercialisation of its 1 kW residential PEMFCs by 2008. This is termed the Dash to 2008 when it is planning on having a unit priced on the open market at less than 1.2 miUion Yen (approximately US 9500). The technical targets for the system are a cold start time of less than 10 minutes, overall efficiency of >77% higher heating value (HHV) and 80°C waste heat. In the new company, TFCPS will produce the stacks. 

Figure 4.8 Fuel choice during 2006 for residential fnel cells [City Gas, which is mainly used in Japan, is a mix of hydrogen and natural gas, with the main component being natural gas.] Source Fuel Cell Today...

Fuel Cells (UTC Fuel Cells). Worldwide, Fuji Electric Company and Mitsubishi Electric Company in Japan developed PAFC systems for residential and stationary power applications. The PAFC demonstration units have been developed for a wide variety of backup power and even transportation applications. In the 1990s Georgetown University helped operate a PAFC bus fueled by reformed methanol. The original stack was produced with a Fuji Electric fuel cell stack, and a second system was installed with an IFC 100-kWe PAFC stack, shown in Figure 7.15. This bus was operated successfully for a number of years and then sent to the University of Califomia-Davis. However, large relative system size and rapid development of the PEFC have since limited development of the PAFC to stationary power applications [37]. 

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