When Ballard Power Systems Inc. first rocketed into public consciousness a decade ago, it had the field of fuel-cell technology largely to itself. No more. Today, at least 50 companies in North America, Europe and Japan are developing fuel cells and related systems and components for the auto industry.

They include virtually all of the major automobile manufacturers, as well as companies such as Hydrogenics Corp., United Technologies Corp., and Nuvera Fuel Cells Inc., which have relationships with other car makers. Together, these companies are spending in excess of $2-billion (U.S.) annually on fuel-cell research and development, an industry official said.

"When government grants are added on, the amount of spending likely tops $4-billion," says Ron Britton, president of Fuel Cells Canada, a Vancouver-based trade association.

Fuel cells convert the energy of a chemical reaction between hydrogen and oxygen directly into electric energy and heat. Environmentally friendly, the technology is seen as a potential alternative to the internal combustion engine.

Based on publicly available information, Burnaby, B.C.-based Ballard is currently the leading developer, ahead of everyone else in terms of data, experience, size of operation and patents. "By any measure you've got," says former Ballard chief financial officer Paul Lancaster, "they're out in front." Mr. Lancaster is now CFO of Palcan Fuel Cells Ltd., which is developing hydrogen storage systems.

But analysts say several U. S. competitors are nipping at their heels, including those like Nuvera, Plug Power Inc. and United Technologies. Prototype vehicles produced by Italian car maker Fiat contain fuel-cell stacks supplied by Nuvera, a privately owned Cambridge, Mass., company with manufacturing facilities in Milan. Nuvera is also supplying gasoline fuel-processing technology to Renault.

Robert Derby, a spokesman for Nuvera, said his company is one of about 10 actually involved in fuel-cell manufacturing. The rest, he said, are producing membranes, catalysts and other fuel-cell components. Those include Hydrogenics of Mississauga, a public company 17-per-cent owned by General Motors Corp.

The strongest competitive challenge is expected to come from Japan. Mr. Britton says Japan has set the most aggressive targets for fuel-cell development. The Japanese government has said it hopes to have 50,000 fuel-cell vehicles on the road by 2010 and five million a decade later. By comparison, the U.S. Department of Energy says it won't be able to make a decision about commercial production until 2015.