Can Hydrogen Cars Be Charged Using Renewable Energy Sources?

The ongoing debate over the future of transportation and energy sources frequently circles around hydrogen cars and their ability to harness renewable energy. This article explores the practicalities and feasibility of charging hydrogen cars with renewable energy sources, comparing it to traditional electric vehicles (EVs).

Understanding the Role of Hydrogen in Cars

Hydrogen cars, also known as fuel cell electric vehicles (FCEVs), are designed to rely primarily on hydrogen as their fuel source. Unlike traditional electric vehicles (EVs) that can be charged using electricity from the grid, hydrogen cars currently lack infrastructure to recharge their batteries in the same way. The presence of a small traction battery in hydrogen cars is to aid in acceleration and hill climbing, but it cannot replace the need for specialized hydrogen fuel cells to provide the necessary power.

Role of Renewable Energy in Hydrogen Production

Though the initial plan was to use renewable energy to produce hydrogen, the current trend is towards using natural gas. This shift has raised concerns about environmental sustainability. Green hydrogen, which is produced from renewable energy sources, is significantly more expensive, costing around $14-16 per kg. This high cost is a significant barrier to the widespread adoption of hydrogen cars.

Producing 1 kg of hydrogen requires approximately 9 liters of water and 50 kWh of electricity. For a car like the Toyota Mirai, which typical refills with 5 kg of hydrogen, this means a total of 250 kWh of electricity is needed to travel 402 miles. In comparison, a 100 kWh electric car can travel 405 miles, showcasing that hydrogen cars require 2.5 times more electricity. This disparity is one of the reasons why, after 10 years of development, the sales of hydrogen fuel cell vehicles (FCEVs) stood at 18,892 in 2022, while battery electric vehicles (BEVs) sold a much higher number of 7.8 million units.

The Challenges of Hydrogen Storage and Efficiency

Hydrogen, being the lightest molecule with the fastest thermal speed, is challenging to store. It is essentially the only matter that Earth loses. Hydrogen is not an energy source; it is an energy carrier. To produce 33 kWh of hydrogen energy, approximately 60-70 kWh of other energy, such as electricity, is needed. Solar energy is the most efficient form of energy conversion to hydrogen, but the efficiency of hydrogen fuel cells is only around 50%, implying that 2 kWh of hydrogen energy requires 4 kWh of other energy.

Conversely, using a battery, which has a higher efficiency of 1.4 kWh of Solar energy for 1 kWh of electricity, is more beneficial. This highlights the inefficiencies and environmental costs associated with producing and utilizing hydrogen as an energy source, despite its renewable potential.

Conclusion: Is It Worthwhile?

While it is possible to charge hydrogen cars using renewable energy sources, the practical challenges and inefficiencies suggest that this approach may not be the most sensible option in the current energy landscape. Renewable energy sources like solar and wind can effectively power electric vehicles, making them a more efficient and cost-effective choice.

The choice between hydrogen and electric cars ultimately depends on various factors, including infrastructure, cost, and environmental impact. As renewable energy technologies continue to advance, battery electric vehicles (BEVs) may remain the superior option for a sustainable future.