The world's smallest home fuel cell (Mitsubishi Heavy Industries)

Competition to develop fuel-cell systems for the home is heating up, and some could be on the market as early as next year. The spread of such systems to generate electricity will help conserve fuel and could slow down environmental destruction. The government is giving full support to these moves and has established a target of meeting 4.5% of all household electricity needs with fuel cells by 2010.

Smaller, Cheaper Systems
Fuel cells for the home generate electricity and hot water when oxygen reacts chemically with hydrogen that has been extracted from natural gas and other fuels. Such cells for motor vehicles have already been developed, and the first fuel-cell-powered automobiles went on sale late last year.

To make them feasible for home use, though, technical improvements were required to ensure a steady supply of electricity and to make the equipment small enough to be placed around the home. Another big bottleneck was cost. These obstacles have now been cleared to a considerable degree, opening the door to commercialization.

An experimental system built by Nippon Oil has been operating at a model home in Yokohama since February. It measures 100 centimeters high, 90 cm across, and 50 cm deep and is small enough to be placed in front of the house. The world's smallest model was later announced in early June by Mitsubishi Heavy Industries; it is 100 cm high, 60 cm across, and 30 cm deep. Both models are expected to go on sale in fiscal 2004 (April 2004 to March 2005) for around ¥500,000 to ¥600,000 (approximately $4,000 to $5,000 at ¥120 to the dollar), placing them within the reach of ordinary households.

The biggest advantage of fuel-cell systems is their eco-friendliness. They rely on a chemical reaction that is electrolysis in reverse, and the only byproducts are electricity and hot water. No carbon dioxide or nitrogen oxides are generated. Fuel-cell automobiles, moreover, are completely nonpolluting, since they use hydrogen that is stored in a tank.

Storing hydrogen near people's homes has raised safety concerns, however, and so household systems will generate the volatile gas from natural gas or kerosene. This process will result in emissions of carbon dioxide, but they will still be 20% less than that generated by thermoelectric power plants.

Tokyo Gas, which also hopes to launch a household model on the market during fiscal 2004, estimates that if fuel cells are used to meet households' entire hot water needs and two-thirds of their electricity needs, consumption of primary fuels can be reduced by 20% and emissions of carbon dioxide and nitrogen oxides cut by 20% and 68%, respectively. An additional 20% savings is anticipated due to the elimination of energy loss during transmission.

There is, moreover, the savings on actual energy costs due to lower consumption. A family of four using the world's smallest home fuel-cell system developed by Mitsubishi Heavy Industries can expect to save ¥50,000 ($417) annually on utility bills.

State Support
Governments in many countries are stepping up their support of fuel-cell systems. Japan's Ministry of Economy, Trade, and Industry has appropriated ¥30.7 billion ($256 million) in the fiscal 2003 budget with the aim of generating 2.1 million kilowatts - equivalent to 4.5% of energy consumed by all households in Japan - with fuel cells (including those for industrial uses) by 2010. The ministry hopes, moreover, to raise the power generated to 10 million kW by 2020. In June, energy officials from around the world gathered in Tokyo for the World Gas Conference. In an address made at the opening ceremony, METI chief Takeo Hiranuma commented that with the rapid development of fuel cells, "society is on the threshold of a hydrogen-energy era."

Competition to develop commercial systems has intensified among companies in such industries as energy, electric machinery, and heavy machinery. Tokyo Gas and Nippon Oil fired the opening volley by announcing their intention to market home systems during fiscal 2004, and other gas suppliers and oil wholesalers have since joined the fray. Behind their enthusiasm lies the fact that the spread of home fuel-cell systems will contribute to higher sales of gas and kerosene as sources of hydrogen.

Other companies are focusing their resources on areas in which they have technological expertise. Toshiba and NEC, for instance, are developing tiny fuel cells for use with their notebook computers, while Toray is preparing to launch a miniature cell for mobile phones.