Hydrogen is the simplest and most abundant element in the universe. It is a major component of water, oil, natural gas, and all living matter. Despite its simplicity and abundance, hydrogen rarely occurs naturally as a gas on Earth. It is almost always combined with other elements. It can be generated from oil, natural gas, and biomass or by splitting water using renewable solar or electrical energy.
Once hydrogen is produced as molecular hydrogen, the energy present within the molecule can be released, by reacting with oxygen to produce water. This can be achieved by either traditional internal combustion engines or by devices called fuel cells. In a fuel cell, hydrogen energy is converted directly into electricity with high efficiency and low power losses.Hydrogen, therefore, is an energy carrier, which is used to move, store, and deliver energy produced from other sources.
Hydrogen car technology, also known as hydrogen fuel cell technology, is a form of transportation technology that utilizes hydrogen as a fuel to power electric vehicles. Unlike traditional gasoline-powered vehicles that rely on internal combustion engines, hydrogen cars use fuel cells to generate electricity.
Here’s how hydrogen car technology generally works:
Fuel Cell Stack: The heart of a hydrogen car is the fuel cell stack. It contains multiple individual fuel cells that combine hydrogen gas (H2) with oxygen (O2) from the air to produce electricity through an electrochemical reaction. Hydrogen gas from the tank is fed into a fuel cell stack, which contains multiple individual fuel cells. Each fuel cell consists of an anode, a cathode, and an electrolyte membrane.
Electrochemical Reaction: In the fuel cell stack, hydrogen molecules are split into protons (H+) and electrons (e-) at the anode. The protons pass through the electrolyte membrane to the cathode, while the electrons flow through an external circuit, creating an electric current.
Hydrogen Fuel: Hydrogen fuel is stored on board the vehicle in high-pressure hydrogen tanks. Typically located at the rear of the car. The hydrogen can be produced through various methods, including electrolysis of water (using renewable energy sources like solar or wind power) or steam reforming of natural gas.
Electric Motor: The electricity generated by the fuel cell stack is used to power an electric motor, which drives the wheels of the vehicle. This makes hydrogen cars zero-emission vehicles in terms of tailpipe emissions since the only by-product of the fuel cell reaction is water vapour. The electric current generated by the fuel cell powers an electric motor, which drives the vehicle’s wheels. This provides propulsion similar to an electric car.
Regenerative Braking: Like electric vehicles, hydrogen cars can also utilize regenerative braking to recover some of the energy typically lost during braking. This energy is converted back into electricity and stored in the vehicle’s battery or used immediately to power the motor.
Auxiliary Battery: Hydrogen cars often include a small auxiliary battery to store electricity generated by the fuel cell for use during acceleration or other high-demand situations.
Range and Refuelling: Hydrogen cars typically have a similar range to gasoline-powered vehicles and can be refuelled in a matter of minutes, much like conventional cars. This is in contrast to battery electric vehicles, which often have longer refuelling times due to the need for recharging.
The future of hydrogen cars indeed presents both promise and challenges, offering a nuanced perspective on the potential of this technology:
BENEFITS:
Zero Emissions: Hydrogen fuel cell vehicles emit only water vapour and heat as by-products, making them environmentally friendly and contributing to efforts to reduce greenhouse gas emissions and combat climate change.
Longer Range and Fast Refuelling: Hydrogen cars typically have longer driving ranges compared to electric vehicles and can be refuelled quickly, similar to conventional gasoline vehicles, which addresses the range anxiety and long recharging times associated with electric cars.
Diverse Applications: Hydrogen fuel cell technology can be utilized in various modes of transportation beyond cars, including buses, trucks, trains, and even maritime vessels, offering a wide range of applications for decarbonizing transportation.
Energy Storage: Hydrogen can be produced from renewable energy sources and stored for later use, offering potential solutions for energy storage and grid balancing, especially in conjunction with intermittent renewable energy sources like wind and solar.
CHALLENGES:
Infrastructure: One of the most significant challenges facing hydrogen cars is the lack of infrastructure. Building hydrogen refuelling stations requires significant investment, and currently, there are far fewer hydrogen stations compared to gasoline or electric charging stations. This limits the practicality and adoption of hydrogen vehicles, especially in regions with sparse infrastructure.
Production and Distribution: Hydrogen production is primarily reliant on reforming natural gas, which emits greenhouse gases. Alternatively, hydrogen can be produced through electrolysis of water using renewable energy sources, but this method is currently more expensive and less efficient. Additionally, transporting and distributing hydrogen is complex and expensive due to its low energy density and the need for specialized infrastructure.
Cost: Hydrogen fuel cell vehicles are expensive to produce, primarily due to the high cost of fuel cell technology and hydrogen storage systems. As a result, the initial purchase price of hydrogen cars is often higher than that of conventional gasoline or even electric vehicles. Additionally, the cost of hydrogen fuel itself can be relatively high compared to gasoline or electricity.
Energy Efficiency: While hydrogen fuel cells are highly efficient at converting hydrogen into electricity to power the vehicle, the overall energy efficiency of hydrogen cars is lower than that of battery electric vehicles (BEVs). This is because of energy losses in hydrogen production, distribution, and conversion, making hydrogen cars less efficient in terms of energy consumption per mile travelled.
Safety Concerns: Hydrogen is highly flammable and requires careful handling and storage. While hydrogen cars are designed with safety features to mitigate risks, concerns about the safety of hydrogen fuelling stations and the potential for hydrogen leaks or explosions remain a challenge for widespread adoption.
Market Competition: Hydrogen cars face stiff competition from other alternative fuel vehicles, such as battery-electric vehicles and plug-in hybrids. The rapid advancement of battery technology and the growing availability of electric charging infrastructure have contributed to the popularity of electric vehicles, posing a challenge to the market growth of hydrogen cars.
Addressing these challenges will require continued investment in research and development, improvements in infrastructure, advancements in production technologies, and policy support to incentivize the adoption of hydrogen vehicles.
Despite these challenges, hydrogen car technology has the potential to play a significant role in the transition to cleaner transportation systems, particularly in applications where long-range and rapid refuelling are critical, such as heavy-duty trucks and buses. It also offers the advantage of decoupling transportation from fossil fuels if the hydrogen is produced using renewable energy sources.
CONCLUSION:
Cost & Infrastructure: EVs are currently cheaper than hydrogen cars. Ev’s cost lessbecause they use existing infrastructure and don’t require building a new hydrogen economy.
Performance: Hydrogen cars can go farther and refuel faster than EVs.At the same time, hydrogen cars use more energy overall than battery cars. The reason why hydrogen is inefficient is because the energy must move from wire¬to¬gas¬to¬wire to power a car. This is sometimes called the energy vector transition. In other words, the hydrogen fuel cell requires double the amount of energy.
Unlike FCEVs, battery-powered electric vehicles are quite energy-efficient. While FCEVs are less than 40% energy-efficient, most battery-powered electric cars and other vehicles boast around 80% efficiency. This means that for every 100 watts of energy produced, nearly 80 watts will be used to power the vehicle.
Popularity: EVs are currently more popular than hydrogen cars so far.
Environment Impact: Hydrogen cars produce zero emissions, but the production of hydrogen is not always environmentally friendly. If both were charged using renewable electricity, the carbon footprint would be similar.
This exclusive article has been published in Automark Magazine – International, May-2024 printed edition from Pakistan.