Very few car manufacturers are actually spending time researching the internal combustion hydrogen engine. Most prefer to talk about fuel cell batteries. Similarly to conventional electric batteries, fuel cell batteries power an electric motor that turns the wheels. Yet, hydrogen engines may be the most efficient way to embrace a cleaner energetic new era. Or not.

BMW and Mazda are amongst the highest profile manufacturers involved in the development of hydrogen engines. According to them, they are more affordable, more versatile - since they can come in a variety of sizes - and can be powered with different types of fuel. 

BMW recently presented ten hydrogen-powered 7-Series in Toronto. Half of them could be powered using either hydrogen or regular gasoline. According to BMW engineers, it is the ideal transitional technology while waiting for a large-scale hydrogen infrastructure to be developed. 

"It is possible to use one type of fuel or another on the road and the performance of the car does not change," says Jason Perron, director of BMW's CleanEnergy program. "The optimal use of hydrogen is limited, but for now, it is an acceptable compromise."

Perron's comment suggests that, in order to be compatible with gasoline, the 760i's 12-cylindre engine does not use the maximum energy from hydrogen. On the highway, the engine uses between 3 and 4kg of hydrogen or approximately 12L of gasoline per 100km, depending on the fuel used. There is definitely room for improvement.

"With better hydrogen compression, the same power could be produced by a 4-cylindre turbo engine," explains BMW's spokesperson. "Engine management can also be improved through what others call Hybrid Technology." By adding a secondary electric motor, BMW says the efficiency of its hydrogen technology can be doubled. 

A small displacement hydrogen turbo engine would be perfect for BMW's smaller cars, such as the Mini Cooper. Should this technology become widespread, the cost would only be slightly higher than that of today's hybrids.

With so many advantages, the million dollar question would be to know what is preventing the technology from burgeoning. Realistically, with only a few hydrogen stations available in North America, it is almost impossible to fill up with hydrogen. This explains why BMW showcases its 7-Series in large political centres throughout North America.

"We use our hydrogen vehicle as a marketing tool and to spread the news about the technology to governments and to the rest of the industry," confirms Frédéric Dorais, regional sales manager for BMW Canada. He hopes increased knowledge about the technology will motivate governments to promote infrastructures for replacement fuels, such as hydrogen. If produced through renewable sources, hydrogen represents a viable starting point in finding a solution to the energetic and environmental crisis the automotive industry is currently facing.

Presently, the flex-fuel 760i's range is 200km with hydrogen and 500km with gasoline. According to BMW, this will help reduce trips to the hydrogen fuelling station, giving time to gradually build a distribution infrastructure. 

The strategy may work in the State of California, for instance. There, the plan is to create a "hydrogen highway" in the next five years or so. New regulations also require manufacturers to offer at least one zero-emission vehicle if they want to keep selling cars in the West Coast State.