Hydrogen is often presented as the fuel of the future. While fuel cells are the most well-known technology for harnessing this energy, hydrogen internal combustion engines (HICE) offer an interesting alternative. Alpine, with its Alpenglow Hy6 concept car, has chosen this path, demonstrating the potential of this technology.
How does a hydrogen combustion engine work?
The operating principle of a HICE is similar to that of a gasoline engine: a mixture of fuel (hydrogen) and air is compressed in a cylinder and then ignited. The resulting explosion pushes a piston, thereby driving the crankshaft.
However, hydrogen has specific characteristics that require technical adaptations:
- Faster flame and higher temperature: Hydrogen combustion is faster and releases a higher temperature than gasoline. Therefore, the materials used in the engine must be more resistant.
- Need for an excess of air: Hydrogen requires a higher air/fuel ratio for optimal combustion.
- Specific injectors and spark plugs: The injectors must be able to precisely meter the hydrogen, while the spark plugs must generate a more powerful spark.
The advantages of hydrogen combustion engines
- High performance: Hydrogen offers high energy efficiency and allows for significant specific power outputs.
- Reduced emissions: Hydrogen engines primarily emit water vapor and very low levels of nitrogen oxides (NOx). Due to the absence of carbon, they do not produce CO2 during combustion.
- Existing infrastructure: HICEs can be integrated into existing vehicles, which facilitates their deployment.
The challenges to overcome
- Hydrogen production: The production of “green” hydrogen from renewable energy sources is still costly and requires appropriate infrastructure.
- Hydrogen storage: Storing hydrogen on board vehicles remains a technical challenge due to its low volumetric energy density.
- Safety: Hydrogen is a flammable gas, which requires special precautions in terms of tank design and manufacturing.
Future prospects
Hydrogen combustion engines offer an interesting alternative to battery electric vehicles, especially for applications requiring high range and fast refueling times. However, their large-scale development will depend on resolving the challenges related to hydrogen production, storage, and distribution.
Conclusion
Hydrogen combustion engines represent a promising path for the decarbonization of transport. Although technical challenges remain, the progress made in this field is encouraging. By choosing this technology for its Alpenglow Hy6 concept car, Alpine is helping to accelerate the development of this innovative solution.
Keywords: hydrogen engine, HICE, Alpine, Alpenglow Hy6, hydrogen, internal combustion, clean vehicle, environment, energy, sustainable mobility.