The idea of a hydrogen-powered car racing at the 24 Hours of Le Mans is one step closer to reality with the Automobile Club de l’Ouest revealing its latest prototype concept for 2025.
The ACO and GreenGT’s Mission H24 project first bore fruit in 2018 with the launch of the LMP2HG prototype, which turned demonstration laps and utilised hydrogen refuelling technology. It was also seen in two rounds in the Le Mans Cup Series, racing in the Innovative category, but sharing the track with LMP2s LMP3s GT3s.
Lessons learned from the LMP2HG were used to develop the H24. This car was also based upon an ADESS LMP3 platform, and it was introduced in the year 2021. It had upgraded brakes and transmission systems. The H24 was also in the Le Mans Cup, but always at a distance from the front.
The third-generation Mission H24, whose name is up for public suggestions, is designed push the limits of hydrogen powertrains with the goal to match GT3 machines that will begin racing at Le Mans in the next few months.
Power comes from electrochemical reactions in the stack of Symbio hydrogen cells that convert the fuel’s chemical energy into electricity, as well as heat and water by-products.
Two Plastic Omnium tanks will be fitted to the car, with each tank able of holding 3.9kg hydrogen under 700bars. This would make the total weight of 100kg. This is intended to last between 25 and 30 minutes under racing conditions. Compare this to the 40 and 50 minute stints LMP2s or Hypercars usually do at Le Mans.
TotalEnergies and the ACO are working together to create the infrastructure for hydrogen refuelling required by Le Mans. Under the Mission H24 project, the French company developed the world’s first mobile hydrogen refuelling station to be used at racetracks.
Since the H24, the power delivery to the rear wheels was refined from two motors to one motor. This resulted in a weight reduction of 18kg. The future prototype will have a maximum output of 650 kW, higher than today’s Hypercars, while the motor will have a power density of 20 kW/kg.
The motor’s operating range can be increased, allowing a single unit. A 400kW lithium battery, 12kg lighter than the H24’s equivalent, will recover the car’s braking energy and provide some power to the motor.
German constructor ADESS continues to supply the chassis for the prototype of third-generation hydrogen. The cockpit will have a central position, and the cell stacks, fuel tanks and the motor will all be behind the driver. The windscreen extends along the entire front of the vehicle, with cooling vents either side.
It is intended to achieve a maximum of 1300kg. This will reduce the weight by 150kg. Hypercars can’t be less than 1030kg. However, their final weight depends on the Balance of Performance.
The general design of the hydrogen prototype is expected to be finalised by March, potentially enabling a mock-up to be ready for presentation at next year’s 24 Hours of Le Mans.
In October 2024 the most important bench testing of power units will begin, followed by car assembly in early 2025 and the first shakedown.
‘Thanks to MissionH24, hydrogen technology has stood out in the competition world,’ said project technical director Bassel Aslan.
‘Now the time has come to prove that this technology can offer an alternative to fossil fuels with the same efficiency and zero CO2 emission.
‘This new car will be for those involved the real symbol of the future of motorsport in line with the energy transition.’
Mission H24’s third-generation car will continue the trend of testing hydrogen fuel cell technology, although the ACO has opened its future hydrogen racing class up to vehicles powered by hydrogen-fuelled internal combustion engines.
ACO is one of the main players in the motorsport industry in adopting hydrogen technology. Its aim of introducing a new class in the coming years gained momentum when Toyota revealed a hydrogen fuel cell prototype concept at this year’s 100th anniversary Le Mans edition.
The FIA Extreme H Championship could beat the ACO to the punch in terms of introducing a competitive class of hydrogen racing if it debuts on time 2025.
‘After introducing hydrogen to the racetrack, MissionH24 is now entering a new phase: bringing hydrogen to competitive racing,’ said ACO President Pierre Fillon.
‘This new prototype clearly intends to rival the other forms of energy in the field. The technology of hydrogen is safe, reliable, and can perform.
‘The ambition is now to provide the first zero-emission winner of the 24 Hours of Le Mans.’
The article New Concept Brings Hydrogen Closer to Le Mans first appeared on Racecar Engineering.