Mergeing environmental innovation,
performance with hydrogen engine tech

(May 11, 2024) Under the spotlights of the 2022 Paris Motor Show, Alpine presented its Alpenglow concept, a veritable manifesto of the brand's future directions in design and sustainable innovation, the "mother of all future Alpines." This founder model embodied the brand's ongoing research into hydrogen-powered combustion engines for sports cars, with the potential for high performance both on the road and in competition, in line with the brand's ambitious decarbonization targets. Alpine is therefore ready for possible changes in future regulations.

Today, the Alpine Alpenglow Hy4 is no longer just a concept car, but has become a genuine rolling lab designed as a racing car with its carbon monocoque and turbocharged 2.0-liter 4-cylinder engine develops 340 bhAfter a presentation within the confines of the circuit May 10, Alpine Alpenglow Hy4 will make its public debut today (May 11) before the TotalEnergies 6 Hours of Spa-Francorchamps Endurance Race (FIA WEC) and its 70,000-plus spectatIt will be the perfect opportunity to demonstrate to motorsport enthusiasts how a hydrogen-powered internal combustion engine perpetuates the sounds and vibrancy that are the emotional aspects of a racing car.

The feeling is intensified by the very spectacular design of the Alpine Alpenglow Hy4, which is further enhanced in this version. Alpine Alpenglow Hy4 will also make demonstration runs during the 92nd edition of the 24 Hours of Le Mans June 14 and 15.

The significance of the name Alpenglow takes on its absolute meaning with this rolling lab: the optical phenomenon that casts a glowing light over the mountains before sunrise perfectly symbolizes the dawn of a new world.


"As part of our active participation in decarbonizing motorsports, we see the hydrogen internal combustion engine as an extremely promising solution. We know that hydrogen will be an essential step in decarbonizing the next generations of Endurance cars, and could also be for Formula 1 cars, particularly by switching to liquid storage for greater compactness and performance. The Alpenglow prototype perfectly illustrates this, a genuine technological laboratory for developing tomorrow's hydrogen engines," said Bruno Famin, VP Alpine Motorsports.

The hydrogen solution is being considered in various ways throughout the Renault Group, contributing to its carbon neutrality objectives in Europe by 2040 and worldwide by 2050.

    •    With HYVIA (a joint venture with Plug), Renault Group offers a complete and unique ecosystem that includes fuel cell-powered light commercial vehicles, hydrogen recharging stations, fleet financing, and maintenance services.

    •    Renault Group is also developing hydrogen combustion engines for high-powered extra-urban commercial use and specific sportier purposes.

    •    The Renault brand is also developing a hybrid technology that combines an electric motor with a hydrogen range extender powered by a fuel cell.

    •    Alpine firmly believes in the role of motorsport as an accelerator for the development of future mobility technologies. The hydrogen-powered internal combustion engine is a tremendously promising solution for racing and road use. Alongside the rolling hydrogen version of Alpenglow, Alpine is gearing up for some exhilarating times with the launch of seven new electric models between now and 2030, starting this year with the A290, its sporty city car and the first electric model from the Alpine Dream Garage.

Exterior design
Alpine Alpenglow is a seminal prototype for the design of the brand's future models. Very close to the 2022 concept, the Alpine Alpenglow Hy4 rolling lab is even better proportioned, the form following the function, with a redesigned crash box (element for absorbing impact energy), an enlarged interior to accommodate two seats, and greater height, while retaining the locations of the hydrogen tanks still located in the side pods and behind the cockpit.

The tracks have been widened to 2.10 m for a total width of 2.15 m, a length of 5.20 m and a height of 1.10 m: ideal proportions. The visual connection has thus been established with the Alpine A424 competing in the prestigious Hypercar category of the World Endurance Championship.

The front end of the hydrogen-powered Alpine Alpenglow is designed to evoke the sensation of a comet arriving from outer space, its speed and penetration of the atmosphere suggested by the 'cosmic dust' light particles in the four front lights and the magenta-colored dorsal contour. The latter turns blue as it reaches the rear of the prototype, as do the vertical lights next to the vertical titanium exhaust pipes, symbolizing the hydrogen and water vapor that its combustion emits.

The aerodynamic aspects of this prototype are an integral part of its design and have been the subject of an ongoing dialogue between Design and Engineering. In a subtle compromise between speed and downforce, the front splitter has been redesigned, creating a vast low air intake that flows over the cockpit and tapers at the rear like a drop of water, letting the airflow under the rear deck. New NACA air intakes are integrated to serve the oil and water radiators, and the snorkel takes on a shape closer to that of a racing car.



The long-tail rear end is reminiscent of the Alpine A220 racing car of the late 1960s. Alpine Alpenglow Hy4 uses the low, transparent spoiler first seen on the concept car for its hydrogen-powered rolling version. The rear diffuser has been redesigned for greater aerodynamic efficiency.

Every design element has been thought through to the finest detail, like the wheel rims with a structure and gradient that evoke speed even when stationary, in perfect harmony with the bespoke tires produced by Michelin, whose graphics match the design of the rims. On the classic carbon bodywork, the centerboard and snorkel are designed in forged carbon, revealing the raw material, like an evocation of the mineral world of the mountains, a typical Alpine element.

Like the exposed technical parts accessible to the outside eye, an air intake is open to the cockpit, giving a glimpse of the onboard ambience, highlighted by a triangle of light that energizes the concept's styling even further.

Hydrogen power: 340 HP that roars

The Alpine Alpenglow hydrogen-powered rolling lab is designed like a racing car with an LMP3 carbon chassis. Under the Alpine Alpenglow Hy4 carbon bonnet is a 2.0-liter in-line 4-cylinder turbocharged development engine delivering 340 bhp. It is fueled by hydrogen (more precisely, H2 dihydrogen) with direct injection at 40 bar pressure and water injection to reduce NOx emissions. It can reach a maximum of 7,000 rpm and is coupled to a sequential racing gearbox with a centrifugal clutch. The performance is comparable to the petrol equivalent, with a top speed of approximately 168 mph.

Developing such an engine requires very specific work because hydrogen is injected in gas form, making it more challenging to create a homogeneous mixture than petrol, which is injected in droplet form. Hydrogen can burn at a much more comprehensive range of concentrations, from 4% to 76%, with both lean and rich mixtures.

In all cases, abnormal combustion must be avoided, which means preparing a homogeneous mixture and controlling the temperature in the combustion chamber. The adaptation work carried out on the Alpenglow engine Hy4 has contributed to enriching the expertise of Alpine Racing engineers in the development of a new Alpine engine entirely designed to be hydrogen-powered, with the presentation of a second rolling version before the close of 2024.

The three Alpenglow tanks Hy4 store hydrogen in gas form 2.1 kg (4.62 pounds) each under high pressure: 700 bars. They are located in the side pods and aft of the cockpit, in ventilated compartments and sealed off from the interior. A pressure regulator reduces the pressure from 700 to 200 bars before lowering it to 40 bars with direct injection into the combustion chamber.

Numerous measures have been taken to ensure absolute safety. Composite cylinders under 700 bars are "Regulation 134" certified, valves are installed for rapid evacuation in the event of a fire, hydrogen presence sensors keep a constant watch, a rigorous start-up procedure is in place with numerous checks. Finally, a color-coded system alerts the driver and emergency services according to the degree of urgency of each type of incident.

There are no plans to put the Alpenglow into production, but with Renault Group already developing hydrogen combustion engines and the ACO set to authorise hydrogen-powered racers from the 2027 24 Hours of Le Mans onwards, it will be fascinating to see where this prototype leads.