MONTREAL -- A revolution in how the world travels could be less than a decade away as some of the largest companies compete to develop hydrogen-powered vehicles that will reduce the reliance on foreign petroleum.

Insiders say the stakes in hydrogen-vehicle production race are huge as governments try to reduce pollution and greenhouse gases that threaten the environment.

More than 1,000 researchers, companies and government leaders gathered Monday for a four-day conference to discuss advances in hydrogen technology.

Tapan Bose, an organizer of the World Hydrogen Energy Conference, said a role model is California, where 10 per cent of all cars sold by 2005 must have no emissions.

"Canada started out as a leader but I'm not sure it's still a leader because it's not as focused as some of the other countries, like the United States and Japan,'' Bose, president of the Canadian Hydrogen Association, said in an interview.

In recent years, millions of dollars have been spent in the search for a breakthrough that will make the environmentally clean technology commercially viable.

One example, cruising the streets of Montreal as the conference got under way, was a Ford Focus, modified with a hydrogen fuel cell. Other cars passed the vehicle by but actor Dennis Weaver, who was behind the wheel, said he liked it.

"It was really quiet and moved out with a lot of zip,'' said Weaver, known to TV audiences as the horse-riding urban cop Sam McCloud. "Hydrogen is the oil of the future.''

Conference participants said the burning of hydrogen does not produce harmful byproducts such as carbon, mercury and sulphur, found in fossil fuels.

"The benefits of a hydrogen future would change the world and solve many of our most vexing problems,'' said David Garman, associate U.S. secretary of energy.

Garman said it will take years to develop needed technology and will require intense global co-operation to develop standards.

"This is not a sprint,'' he told 1,000 conference delegates. "This is a marathon.''

Ford has turned to fuel cells to power its vehicle prototypes.

Plans call for production of commercial and government fleets to begin in 2004. Other customers may have to wait until 2012.

"It will take a while,'' said Philip Chizek, marketing and sales manager for Think Technologies, the fuel cell division of Ford.

"It's no silver bullet but we are getting down a learning curve.''

However, German automaker BMW doesn't foresee fuel cells being the solution for its speedy sports cars. Instead, it has focused on using hydrogen as the main energy source using the internal combustion engine.

"We're thinking that fuel cells are not the right thing to propel cars but just used as electrical power units,'' said spokesman Tobias Nickel.

Its hydrogen-powered car travels 215 km/h using hydrogen with no emissions. The car could be on the market in five to seven years, although the price of hydrogen now is prohibitively high.

Nickel said fuel cells might be better for small cars and buses that can carry large tanks filled with compressed hydrogen.

No single approach will be the solution, said John Wallace, head of Ford's hydrogen vehicle research and development.

"It isn't just a matter of showing people that we can make vehicles and take them around the block. We have to develop fuel cell vehicles that meet all those customers' expectations.''