The zero-emission car that comes from space

Used as a matter of course in the space industry, fuel cells are of more and more interest to car manufacturers in their quest for a zero-emission car.

 

Honda is currently marketing the first production car to draw its energy from a fuel cell. To promote this initiative, the Japanese manufacturer has no hesitation in putting the spotlight on certain of its better known customers as, in this case, with the actress Jamie Lee Curtis. Credit: Honda

Once part of their prestigious technology showcase, zero-emission vehicles are becoming a priority for the manufacturers. True, petrol and diesel will continue to dominate the car scene for a while longer, but tomorrow’s car will be emission-free or will no longer exist which is why certain of the big makes are considering fuel cells.

Technology developed by the space industry
The fuel cell works via inverse electrolysis which, with hydrogen and oxygen, produces electricity and heat. The “waste” from this reaction is... water! A technology which, on paper, enables a zero-emission car to be developed as it will not release CO2 (greenhouse gas) or pollutant particles. Obviously, this is not the only way to create a zero-emission vehicle, but over recent years some of the major manufacturers like Honda, Toyota, Renault-Nissan, Ford, General Motors, PSA and Mercedes have made significant progress.
The principle of the fuel cell was discovered in 1839 by the German Christian Schönbein. But the process remained complex (requiring the manufacture of hydrogen) and, above all, costly in comparison with the more classic formulae. However, in the 1960’s, with the space race, the fuel cell came back into being, as its operating mode was of utmost interest to the human flight spacecraft designers. In the United States, the Apollo programme developed the necessary technological improvements with considerable means. So, although the fuel cell was not invented for the space industry, it owes a great deal to its evolution; an evolution that continued, notably through NASA and the space shuttle. Several recent government programmes to encourage the development of fuel cell based solutions have even been launched in, for example, Canada, Europe and the United States.

The space shuttle uses fuel cells to produce all the electricity that it requires. When docked with the Station, it does, however, use additional power provided by the orbital complex’s solar array. Credit: NASA

Laptops before cars?
A car using a fuel cell does, however, pose a few specific problems. First and foremost is that of the safety of its hydrogen tank (the explosion hazard is far from inexistent) and that of its filling (highly volatile, hydrogen requires a leaktightness beyond reproach). These can be solved by combining the hydrogen with methanol which will make storing and filling much easier. But, it would then produce greenhouse gases (CO2) again!
Honda, on the other hand, has recently launched the FCX Clarity, the first production car to run exclusively on hydrogen. We would point out that this offer from the Japanese manufacturer remains, in the United States, limited to the state of California (hydrogen filling stations being few and far between) and takes the form of a $600 a month lease agreement over three years for a fleet of 200 sedan cars. The initiative does, however, have the merit of existing and many see it as progress. Nevertheless, the electricity which comes from hydrogen will most probably reach laptops and portable telephones before cars, as, faced with the growing needs in electrical energy of these electrical devices, miniaturised fuel cells would seem inevitable as a future solution.
In conclusion, we would reiterate that hydrogen is an energy carrier and not an energy source as a lot of electricity is required to produce it. So if we want the fuel cell to remain a zero-emission solution, the production of its “fuel” (hydrogen) will have no option but to resort to means that respect the environment, otherwise we will only be moving the problem of pollution.

Publié le 29 juillet 2009