Motorsport Week takes a dive into the technical details of the recently-named H24EVO model from the ongoing MissionH24 project which aims to bring hydrogen to Le Mans in the upcoming years.
The future of motorsport is a subject of curiosity, fascination and intrigue.
Motorsport series around the globe are making efforts towards a reduced carbon footprint, through factors such as travel logistics and using sources of renewable energy during race weekends.
The FIA World Endurance Championship has been using 100% renewable fuel by TotalEnergies since the beginning of 2022, composed from wine residue waste from the French agricultural industry, which set about reducing the emissions of each car by at least 65% – an impressive feat for a championship with a field up to 37 cars, and over 60 at the Le Mans 24 Hours.
Since the WEC’s inception in 2012, manufacturers have used electric-ICE hybrid powertrains in the premier LMP1 and Hypercar categories, aligning a noticeable presence of hybrids within the automotive industry.
Up to 22.6% of the market in 2022 were hybrids, according to the European Automotive Manufacturers’ Association. Unsurprisingly, a road car package incorporating the best of both electric and ICE, with reduced emissions as a result, lends to an appealing product, aside from the added weight compared to solely ICE equivalents.
For now the next step awaits, and the Automobile l’Ouest (ACO) – who governs and organises the historic 24 Hours of Le Mans – thinks that is hydrogen.
As reported by other publications, a hydrogen-only class at Le Mans has been delayed until 2027.
The ACO begun their partnership with GreenGT in 2018, with a model which has been gradually developed and ran four rounds of the 2022 Michelin Le Mans Cup, operating at the performance levels of a GT3 car, and with the current focus still aligned on the quickest GT3 cars.
After testing essential function on the two existing hydrogen cars, first LMPH2G and then H24, accomplished specific stages of the research and development phase of the project such as “burn-in testing of the new power unit (hydrogen cell system, tanks, electric motors, battery, etc.) on laboratory cars”.
After testing essential functions on these cars, as the final product will need to rival other forms of energy with competitive pace to show for it, and appeal to customers such as potential manufacturers.
A Symbio hydrogen cell system will be used in the H24EVO, aiming for a 50% high power density and a maximum net power output of 300kW (402 mechanical horsepower).
The latest H24 model claims to have improved on the volume and weight distribution of the hydrogen (H2) tank, meeting the demands of a race car without significantly compromising performance as the tank is depleted.
Plastic Omnium is the ACO partner who will supply the two internationally certified H2 tanks, each storing 7.8 kg (3.9×2) of hydrogen at 700 bars of pressure, totalling around 100 kg.
In 2018, at the 4 Hours of Spa, Total Energies publicly demonstrated the refuelling process. In the following year, they created the world’s first mobile H2 filling station which was designed to travel with the team from circuit-to-circuit.
TotalEnergies are currently working with the ACO on the infrastructure which will introduce refuelling for the H2-only Le Mans class in 2027.
Powertrain and chassis
The H24EVO consists of the single-ratio gearbox and a single electric motor powering the rear wheels, as opposed to the outgoing H24 model which uses two electric motors for the rear axle.
Power density will be greater than 20kW/kg, which they claim is greater than the current F1 MGU-K (approx. 16 kW/kg)
Target max. weight: 30 kg in comparison to 48 kg on the outgoing H24 model
Limited-slip differential supplements drivetrain
ADESS will construct the chassis following the LMP-type structure seen on the outgoing models.
Besides a more optimised cooling system, the driver will be seated more centrally in order to leave spaces on the sides for aerodynamic and cooling purposes.
Target max. weight 1300 kg compared to the 1450 kg of H24
The lithium battery will provide most of the dynamic power, whilst recovering kinetic energy through braking.
The maximum power output will be 400kW (536 horsepower) and the weight of the battery will be at 80 kg, in comparison to 92 kg in the current H24.
It will utilise Michelin tyres specified from 40% biosourced or recycled materials by 2030 in its tyres, and 100% by 2050, although this was a recurring commitment by the H24 project.
Targets and deadlines
A 1300 kg and a 320 kph top speed show the project’s great ambitions to demonstrate hydrogen as a feasible zero energy alternative compared to the existing forms.
This specific model consists largely of deadlines and theory at the moment, and will require years of effort to come to fruition in addition to the developments so far.
Nevertheless, it is one of hope and promise for the ACO to show that Le Mans could safely welcome hydrogen cars to the famous endurance motor race.
March 2024: General design finalised
June 2024: Mock-up
From October 2024: Power unit assembly and bench-testing
From January 2025: Car assembly and first circuit tests