About Solid Oxide Fuel Cells

SOFC System Configuration

A SOFC system consists of a power generation unit and a backup heat source unit.
The power generation unit generates electricity and at the same time recovers the exhaust heat generated during power generation and stores it as hot water in the hot water storage tank. The hot water in the hot water storage tank is mixed with water, heated according to the set temperature by the backup heat source unit, and used for hot water supply.

SOFC Cell Structure and Stack

The smallest component of a fuel cell system is called a “cell,” which consists of an electrolyte (a substance that allows only ions to pass through it) sandwiched between the anode and the cathode. By sending hydrogen or oxygen to these two electrodes (the anode and the cathode), a chemical reaction is caused to occur, producing electricity and heat.

In terms of structure, SOFCs are divided into tubular and planar types.
The tubular type has the advantage of resistance to thermal stress, while the planar type, when the cells are stacked, has the advantage of higher power density than the tubular type. The systems available from Osaka Gas employ a flat-tube type that offers the advantages of both tubular and planar types.