Clean car

Five hundred kilometres
with zero emissions

Resulting from one of the many European projects to develop clean vehicles supported by the JOULE programme, FEVER is one of the first prototypes of an electric car powered by a fuel cell, which consumes only hydrogen and atmospheric oxygen. With a range of 500 km, its top speed is 120 km/hour.

"In 15 to 20 years time, 75% of cars on the road will consist of hybrid vehicles, in which electric power is coupled with an internal combustion engine. The remaining 25% will be fully electric," Gaston Maggetto confidently predicts. A lecturer in electrical engineering at the Université Libre de Bruxelles, he is also president of AVERE (the European association of electric road vehicles) whose 500 or more members include research centres, car companies, energy suppliers, parts manufacturers and users.

From 29 September to 3 October this year, AVERE and its US and Asian counterparts held the 15th worldwide electric vehicle symposium (EVS15). The star attraction at this gathering of the experts was the French manufacturer Renault with the first public presentation of the FEVER demonstration vehicle - one of the first experimental electric vehicles with an engine powered by a fuel cell. FEVER is the result of a European project, coordinated by Renault, which began in 1993 and ended last June.

Electrolysis in reverse

"The fuel cell principle is the reverse of electrolysis, in which a current causes water to break down into hydrogen and oxygen," explains Jean-Claude Griesemann, who leads the research at Renault. "In a fuel cell, it is the recombining of hydrogen with the oxygen in the air which produces an electric current and water." With the aid of a catalyst, the hydrogen introduced into the first chamber in the fuel cell releases electrons, which are captured by a metal plate resulting in an electric current. The hydrogen nuclei - or protons - then pass through a semi-permeable membrane and recombine, in the second chamber, with the oxygen in the air. The water thus formed is the only waste produced by this 100% clean system of energy production.

Two problems remain to be solved: size and cost.

Renault's partners on the FEVER project were the Italian companies De Nora (responsible for fuel cell production) and Ansaldo (assembly of secondary systems and hydrogen tank with the fuel cell), Air Liquide of France (manufacture of the hydrogen tank), Volvo of Sweden (simulations) and the Paris School of Mines (definition of the system's operating parameters). "The main problems were in understanding the physical phenomena which take place inside the system," explains Jean-Claude Griesemann. One of the difficulties is in maintaining the balance between the pressures of air and hydrogen (3 atmospheres) on either side of the membranes during all the transitional stages. Any sudden imbalance could break the membranes - and thus destroy the cells. Another difficulty is linked to managing the water, both that required for gas humidification and cooling and the water produced by the fuel cell. Too much water in the circuits would prevent proper gas circulation for example. Temperature control is also a problem, because any heating means energy consumed at the expense of electricity production."

The lessons of a prototype

The experimental vehicle, which used a modified Renault Laguna estate, demonstrated the feasibility, and above all the qualitative and quantitative performances, of such a system: zero emissions, much higher energy production than for internal combustion engines, a top speed of 120 km per hour and a range which is limited only by the quantity of hydrogen carried (500 km for 8 kg of liquid hydrogen). The remaining problems to be solved prior to industrial production are space (the system's current size only leaves room for two passengers) and cost. "The project was launched five years ago," pointed out the Renault director, "and the fuel cell provided by our partner De Nora reflects the state of the art in 1995. Since then, fuel cell sizes have been reduced four times. Now we are also beginning to master the technologies needed to reduce fuel cell cost." The objective viewed as economically reasonable would be to get down to 100euros/kw, which is equivalent to twice the price of the engine - some good quality fuel cells at present cost up to 100,000 euros/kw.

Ongoing European support...

In addition to working on the FEVER project - a great success at the EVS15 show - Renault, De Nora and Air Liquide are also cooperating with other partners on the EU's HYDRO-GEN project. Coordinated by the French car manufacturer PSA, this aims to develop another type of vehicle using a new generation of fuel cells and compressed hydrogen. "It is becoming increasingly likely that in future the centre of a number of major European towns will only be accessible to vehicles with zero polluting emissions. I am convinced that fuel cells will have a great future after 2010," believes William Borthwick, the scientific officer responsible for the project at the European Commission. In addition to HYDRO-GEN, European programmes are also supporting projects such as FCBUS (the fuel cell bus), coordinated by Air Liquide, and CAPRI, an initiative coordinated by Volkswagen which is based on a new method of hydrogen supply.

An experimental vehicle, modelled on a Renault Laguna estate.

The mass production of this explosive gas, together with its transport and distribution, is in fact one of the main obstacles to use of the fuel cell. Manufacturers are therefore looking at the possibility of producing the hydrogen directly in the vehicle itself by means of a "reformer". A common operation in gas industries, reforming involves oxidising a hydrocarbon, using high-temperature steam and air, and a catalyst, in order to obtain hydrogen, carbon monoxide and a lighter hydrocarbon. With methanol, the reformer produces hydrogen and carbon dioxide only. "This solution has the advantage that it can be used immediately in the existing distribution network," points out Gaston Maggetto. "Methanol can also be produced from very diverse sources. Vehicles designed in this way would no longer be zero emission, but the system's excellent energy efficiency would still result in a major reduction in the CO2 emissions of these vehicles. In any case, producing large quantities of hydrogen would mean building a power station somewhere."

... in the face of vigorous competition

For Renault, as for a growing number of motor manufacturers, the electric vehicle is an important part of development strategy. "And if we forget," remarks Jean-Claude Griesemann ironically, "Toyota's Prius will remind us." While the major obstacle to the growth of the electric vehicle market is its price, the Japanese manufacturer is on the point of launching a hybrid vehicle, first in the US and then in Europe. It attracted a lot of attention at EVS15 and costs no more than a traditional vehicle.

That said, users must still accept this radical change in technology. "In the medium term, the future of the electric vehicle will partly depend on the acceptance of the city-car concept," points out William Borthwick. Following EVS15, a very special kind of rally took a group of electric vehicles from Brussels to Monte Carlo, stopping off to give a demonstration in some 15 towns along the way. The trip (in which bicycles also took part, proving particularly effective when crossing the snowbound Saint Gothard pass) was an opportunity for the public to take a closer look at these "eco-vehicles".

Contact
Jean-Claude Griesemann
Research Department - Renault
Tel.: +33-1-34953495
Fax: +33-1-34957713