Can a Combustion Engine Be Converted to Hydrogen Power?

The transition from traditional gasoline combustion engines to hydrogen-powered propulsion is a topic of great interest for both enthusiasts and engineers. This article explores the feasibility, challenges, and potential solutions for converting a combustion engine to run on hydrogen.

The Ineffectiveness of Converting Multi-Cylinder Piston Engines

One of the primary challenges in converting a multi-cylinder piston engine to run on hydrogen is the spontaneous ignition of hydrogen in the intake manifold. Hydrogen molecules are highly reactive, and they ignite more easily than other fuels. For this reason, traditional combustion engines are typically not suitable for hydrogen fuel.

Success with Wankel Rotary Engines

A notable exception is the Wankel Rotary engine, which has proven to run efficiently on hydrogen. For instance, a Mazda B2200 Ute was successfully repowered with a 13B rotary engine and operated using a triple-fuel system: petrol, CNG, and hydrogen. The vehicle performed excellently on hydrogen, though the primary challenge was the storage of hydrogen.

Storage Challenges

Hydrogen molecules are extremely small and can pass through the steel walls of conventional storage tanks. Addressing this issue was crucial for the success of the project. Unfortunately, by the time the research was discontinued, the problem of hydrogen leakage had not been fully resolved.

Cost and Safety Considerations

While it is technically feasible for an engineer to convert a gas-powered engine to a hydrogen engine, there are significant cost and safety concerns to consider. The conversion involves a complete overhaul of the vehicle's fuel system, including the storage tank and injector system.

Conversion Cost and Performance

According to an engineer, such a conversion is possible, albeit not without costs. A moderate-risk conversion costing a few thousand dollars could result in a low-powered, short-range vehicle that consumes an expensive fuel. The vehicle would also require modifications to the exhaust system, although a catalytic converter is no longer necessary.

For those considering a more cost-effective conversion, the primary issue is the availability and efficiency of hydrogen as a fuel. Hydrogen is notoriously expensive to store and transport, and its energy density is lower than gasoline. This means that the journey cost would be quadrupled compared to using gasoline.

Alternative Solutions: Electric and Hydrogen Fuel Cell Vehicles

Another option is to convert gas-powered vehicles to electric power, then to hydrogen fuel cell vehicles (HFCs). While hydrogen fuel cells are highly efficient, they are still in the early stages of development and adoption. Producing hydrogen through electrolysis at home is one possibility, but it is time-consuming and costly.

Comparative Efficiency

Converting an electric vehicle to hydrogen power by replacing the battery with a fuel cell would be a more efficient approach. This method would waste less chemical energy and offer better performance. However, the availability of hydrogen remains a significant challenge, especially considering the current high costs of production and distribution.

Despite the potential benefits of hydrogen fuel, the infrastructure and technology are still developing. Until hydrogen can be more widely and cost-effectively produced and distributed, converting combustion engines to hydrogen power remains a niche and costly endeavor.

Conclusion: The Future of Hydrogen in Automotive Fuel

The transition to hydrogen-powered vehicles is an exciting frontier in automotive technology. While conversion of existing combustion engines is possible, it presents significant challenges in terms of cost, safety, and efficiency. Advancements in hydrogen storage and production technologies are necessary to make widespread adoption of hydrogen-powered vehicles a reality.