Can Water Be Used as Hydrogen Fuel in Normal Cars?

The idea of using water as a hydrogen fuel source for cars might seem intriguing at first glance. However, the practical challenges are significant. This article explores the concept, the steps involved, and why it might not be as feasible as one might initially think.

The Concept of Hydrogen from Water

The process of extracting hydrogen from water is fundamentally straightforward. In a high school physics class, you can learn about electrolysis, the process of breaking water molecules into their constituent elements, hydrogen, and oxygen. This process, known as water electrolysis, requires applying an electrical current to water, which splits the water molecules into hydrogen and oxygen gases.

Challenges in Storing Hydrogen

While the concept of electrolysis is well-established, the challenges in practical application are considerable, particularly in terms of storage. Hydrogen, while highly efficient, is notoriously difficult to store in sufficient quantities. The space required for a hydrogen storage tank to match the energy density of gasoline in a standard vehicle is enormous.

For instance, to travel the same distance as a car using gasoline, the hydrogen storage tank would need to be about triple the size of the gasoline tank. This makes practical implementation challenging, as it would significantly impact the vehicle's design and utility.

Steps to Use Hydrogen from Water

1. Electrolysis Device

The first step to using hydrogen from water is to have an electrolysis device. A basic electrolysis device can be relatively simple to build. The process involves passing an electrical current through water, triggering the chemical reaction that splits water molecules into hydrogen and oxygen.

2. Storing Hydrogen

The next major challenge is storing hydrogen in a practical and cost-effective manner. Hydrogen must be compressed and cooled to become a cryogenic liquid, which requires specialized and expensive storage tanks.

These tanks are not just costly but also voluminous, making it impractical to rely on such a setup for a car's operation. Additionally, these tanks need to be specifically designed to handle cryogenic liquids, further complicating the implementation.

3. Vehicle Adaption

For a traditional internal combustion engine, minor modifications are needed to adapt to the use of hydrogen instead of gasoline. The fuel system and ignition timing can be adjusted to accommodate hydrogen's properties, which differ slightly from those of gasoline.

For electric vehicles, the process is different. Instead of using hydrogen from water to power a combustion engine, hydrogen fuel cells would be used as a replacement for the battery. These fuel cells generate electricity for the vehicle's electric motor.

Feasibility and Efficiency Considerations

Despite the technical feasibility of using hydrogen from water, practical and economic challenges make it less attractive than other options. For instance, the cost of hydrogen fueling infrastructure and the cost of modifying and maintaining the specialized components required for fuel cell technology are significant.

Another critical point is the energy efficiency. In terms of energy, 100 miles of electricity in a regular electric vehicle (EV) is equivalent to about 50 miles of hydrogen in a hydrogen electric vehicle (HEV) or 25 miles in a hydrogen internal combustion vehicle (HICV). In all cases, it is more efficient to use the electricity directly in the electric vehicle battery rather than converting it to hydrogen and back.

Therefore, it turns out to be far cheaper and far more efficient to simply purchase a regular electric vehicle and harness the direct benefits of electricity for vehicle propulsion.

Conclusion

While the idea of using water as a hydrogen fuel is promising from a theoretical standpoint, the practical challenges, particularly in terms of storage and efficiency, make it less viable than alternative methods. The cost of specialized equipment and infrastructure, along with the sheer inefficiency of the process, make a shift to hydrogen from water a less attractive option.