Between the fuel cell and the internal combustion engine… The heart of IFP Energies Nouvelles (IFPEN) is torn. At its headquarters in Solaize, the research and training organization, working in the fields of energy, transportation and the environment, is studying two solutions for hydrogen. The goal: to find alternative energy for heavy movement equipment such as trucks or construction machinery.

In one of the institute’s rooms, the behavior of the 30 kW fuel cell system (cell core and auxiliary materials) – the test stand that can accommodate up to 210 kW – is first analyzed under different conditions of use. More impressive in size, the combustion engine – an 8-liter diesel adapted to hydrogen – also undergoes calibration work in another room. This is being carried out on behalf of the MH8 consortium, led by Renault Trucks and combining IFPEN, EDF, TotalEnergies and Prisme. Thus IFPEN hopes to achieve the required performance in terms of pollutants (NOx) by tuning the engine. The choice of this technology is soon becoming a reality on the ground as British manufacturer Cummins plans to unveil its hydrogen trucks in the second half of 2022.

To advance its experiments, the institute has also published, in addition to the two seaters, modeling tools for simulating situations.

Battery or motor?

During a display of its test benches, IFPEN also reviewed the advantages and disadvantages of these two carbon-neutral hydrogen technologies in use. According to him, the fuel cell makes it possible to reduce the size of the electric car battery (up to 90%) while providing gains in autonomy and charging time. However, its cost is high and it is far from industrial production. In turn, based on the proven technologies of fossil fuel engines, there is a production tool for the hydrogen internal combustion engine. “Proven durability and ease of maintenance” Adding a Renault Trucks expert to the site. Negative point: the hydrogen engine makes noise and nitrogen oxide (NOx), while the fuel cell is only water. But its emissions are low, “too far from diesel” says Florence Davor, hydrogen combustion engine project manager at IFPEN.

Not forgetting that the cost of hydrogen has an impact on technologies. “The fuel cell solution will have better performance than the thermal solutionexplains Bertrand Gatelier, Head of Automation and Systems Program at IFPEN. In terms of cost of ownership, the cheaper hydrogen is, the more useful a heat engine will be, and vice versa.” The fuel cell also requires a level of hydrogen purity, at least 99.97%, that is not necessary for the combustion engine. In addition, the latter is not sensitive to its external environment. While the intrinsic properties of the fuel cell do not allow it to get into a dusty environment, a temperature above 70/80 ° C and freeze, so as not to damage its membranes. A solution that has no place in the bowels of large construction machinery…