No. 23: On new type fuel cells (1/2) (December 1, 2011)

Basically, there are three kinds of fuel cells depending on electrolyte employed, and the operation temperature varies with the kind of electrolyte. The solid high molecule type that uses polymer electrolyte has an operation temperature of about 80 degrees centigrade. Commercialized in 2009, it uses hydrogen as fuel. It has generation efficiency of about 36%. The phosphoric acid type that uses phosphoric acid solution as electrolyte has an operation temperature of about 200 degrees centigrade. Commercialized in 1998, it uses hydrogen as fuel. It has generation capacity of about 38%. The solid oxide type that uses oxide as electrolyte has an operation temperature of about 800 degrees centigrade. It will be commercialized late 2011, and it uses hydrogen and city gas as fuel. It has generation capacity of about 41%.  

The phosphoric acid type launched in 1998 is a system suitable well for large power demand in the level of 100 kW, and it is installed in schools and office buildings. Lots of efforts are being made to develop the solid oxide type that will be put on the market as the second-generation Ene Farm. The big difference between the solid oxide type and solid high molecule type for household use is the operation temperature. Because the solid oxide type operates at such a high temperature of 800 degrees centigrade, it has various advantages over the solid high molecule type. (To be continued)